auto commit

2018-02-22 14:47:22 +08:00
parent c40ef3cf25
commit 7e4d5152f7
84 changed files with 29405 additions and 4615 deletions
--- a/语法.md
+++ b/语法.md
@ -1,52 +1,52 @@
 <!-- GFM-TOC -->
-* [<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-* [<EFBFBD><EFBFBD>ѯ](#<EFBFBD><EFBFBD>ѯ)
-* [<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-* [<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-* [ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#ͨ<><CDA8><EFBFBD><EFBFBD>)
-* [<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֶ<EFBFBD>](#<23><><EFBFBD><EFBFBD><EFBFBD>ֶ<EFBFBD>)
-* [<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-    * [<EFBFBD>ı<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<23>ı<EFBFBD><C4B1><EFBFBD><EFBFBD><EFBFBD>)
-    * [<EFBFBD><EFBFBD><EFBFBD>ں<EFBFBD>ʱ<EFBFBD>䴦<EFBFBD><EFBFBD>](#<23><><EFBFBD>ں<EFBFBD>ʱ<EFBFBD>䴦<EFBFBD><E4B4A6>)
-    * [<EFBFBD><EFBFBD>ֵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<23><>ֵ<EFBFBD><D6B5><EFBFBD><EFBFBD>)
-    * [<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-* [<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-* [<EFBFBD>Ӳ<EFBFBD>ѯ](#<EFBFBD>Ӳ<EFBFBD>ѯ)
-* [<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-    * [<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<23><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-    * [<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<23><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-    * [<EFBFBD><EFBFBD>Ȼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<23><>Ȼ<EFBFBD><C8BB><EFBFBD><EFBFBD>)
-    * [<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<23><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-* [<EFBFBD><EFBFBD><EFBFBD>ϲ<EFBFBD>ѯ](#<23><><EFBFBD>ϲ<EFBFBD>ѯ)
-* [<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-* [<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-* [ɾ<EFBFBD><EFBFBD>](#ɾ<EFBFBD><EFBFBD>)
-* [<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<23><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-* [<EFBFBD>޸ı<EFBFBD>](#<EFBFBD>޸ı<EFBFBD>)
-* [<EFBFBD><EFBFBD>ͼ](#<EFBFBD><EFBFBD>ͼ)
-* [<EFBFBD>洢<EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<23>洢<EFBFBD><E6B4A2><EFBFBD><EFBFBD>)
-* [<EFBFBD>α<EFBFBD>](#<EFBFBD>α<EFBFBD>)
-* [<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<23><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-* [<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#<23><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
-* [<EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD>](#<23>ַ<EFBFBD><D6B7><EFBFBD>)
-* [Ȩ<EFBFBD>޹<EFBFBD><EFBFBD><EFBFBD>](#Ȩ<>޹<EFBFBD><DEB9><EFBFBD>)
+* [????](#????)
+* [???](#???)
+* [????](#????)
+* [????](#????)
+* [????](#????)
+* [???????](#???????)
+* [????](#????)
+    * [???????](#???????)
+    * [??????????](#??????????)
+    * [???????](#???????)
+    * [????](#????)
+* [????](#????)
+* [????](#????)
+* [????](#????)
+    * [??????](#??????)
+    * [??????](#??????)
+    * [???????](#???????)
+    * [??????](#??????)
+* [?????](#?????)
+* [????](#????)
+* [????](#????)
+* [???](#???)
+* [??????](#??????)
+* [????](#????)
+* [???](#???)
+* [?<3F><>????](#?<3F><>????)
+* [?<3F><>?](#?<3F><>?)
+* [??????](#??????)
+* [??????](#??????)
+* [?????](#?????)
+* [??????](#??????)
 <!-- GFM-TOC -->

-# <EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ????

-ģʽ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>δ洢<EFBFBD><EFBFBD><EFBFBD>洢ʲô<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Լ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ηֽ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϣ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݿ<EFBFBD><EFBFBD>ͱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ģʽ<EFBFBD><EFBFBD>
+????????????????<3F>ě<EFBFBD>???<3F><>???????????????????<3F><>?????????????????????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>޸ģ<EFBFBD>Ҳ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ã<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD><EFBFBD><EFBFBD>Ѿ<EFBFBD>ɾ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>е<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+??????????????????????????????????????????????????????????<3F><>?????????

-SQL<EFBFBD><EFBFBD>Structured Query Language)<EFBFBD><EFBFBD><EFBFBD><EFBFBD>׼ SQL <EFBFBD><EFBFBD> ANSI <EFBFBD><EFBFBD>׼ίԱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӷ<EFBFBD><EFBFBD><EFBFBD>Ϊ ANSI SQL<51><4C><EFBFBD><EFBFBD><EFBFBD><EFBFBD> DBMS <20><><EFBFBD><EFBFBD><EFBFBD>Լ<EFBFBD><D4BC><EFBFBD>ʵ<EFBFBD>֣<EFBFBD><D6A3><EFBFBD> PL/SQL<EFBFBD><EFBFBD>Transact-SQL <EFBFBD>ȡ<EFBFBD>
+SQL??Structured Query Language)????? SQL ?? ANSI ???????????????? ANSI SQL?????? DBMS ??????????????? PL/SQL??Transact-SQL ???

-# <EFBFBD><EFBFBD>ѯ
+# ???

-SQL <EFBFBD><EFBFBD><EFBFBD>䲻<EFBFBD><EFBFBD><EFBFBD>ִ<EFBFBD>Сд<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݿ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ<EFBFBD>Ƿ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ھ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> DBMS <20>Լ<EFBFBD><D4BC><EFBFBD><EFBFBD>á<EFBFBD>
+SQL ????????<3F><><EFBFBD><EFBFBD>???????????????????????????????????????? DBMS ??????<3F><>?

 **DISTINCT**

-<EFBFBD><EFBFBD>ֵֻͬ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD>Ρ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>У<EFBFBD>Ҳ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>˵<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>е<EFBFBD>ֵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD><EFBFBD>
+????????????<3F><>??????????????<3F><>????????????<3F><>????????????????

 ```sql
 SELECT DISTINCT col1, col2
@ -55,9 +55,9 @@ FROM mytable;

 **LIMIT**

-<EFBFBD><EFBFBD><EFBFBD>Ʒ<EFBFBD><EFBFBD>ص<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ<EFBFBD><EFBFBD>ʼ<EFBFBD>У<EFBFBD><EFBFBD><EFBFBD> 0 <20><>ʼ<EFBFBD><CABC><EFBFBD>ڶ<EFBFBD><DAB6><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ<EFBFBD><CEAA><EFBFBD>ص<EFBFBD><D8B5><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+????????????????????????????????????????????<3F><>??? 0 ????????????????????????????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ǰ 5 <20>е<EFBFBD> SQL<EFBFBD><EFBFBD>
+????? 5 ?<3F><>? SQL??

 ```sql
 SELECT *
@ -71,7 +71,7 @@ FROM mytable
 LIMIT 0, 5;
 ```

-<EFBFBD><EFBFBD><EFBFBD>ص<EFBFBD> 3 \~ 5 <EFBFBD>У<EFBFBD>
+????? 3 \~ 5 ?<3F><>?

 ```sql
 SELECT *
@ -79,22 +79,22 @@ FROM mytable
 LIMIT 2, 3;
 ```

-**ע<EFBFBD><EFBFBD>**
+**???**

 ```sql
-# ע<EFBFBD><EFBFBD>
+# ???
 SELECT *
-FROM mytable -- ע<EFBFBD><EFBFBD>
-/* ע<EFBFBD><EFBFBD>1
-   ע<EFBFBD><EFBFBD>2 */
+FROM mytable -- ???
+/* ???1
+   ???2 */
 ```

-# <EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ????

-**ASC**<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ĭ<EFBFBD>ϣ<EFBFBD>
-**DESC**<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+**ASC**??????????
+**DESC**??????

-<EFBFBD><EFBFBD><EFBFBD>԰<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>н<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+?????????<3F><>???????

 ```sql
 SELECT *
@ -102,9 +102,9 @@ FROM mytable
 ORDER BY col1 DESC, col2 ASC;
 ```

-# <EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ????

-<EFBFBD><EFBFBD>Ӧ<EFBFBD>ò<EFBFBD>Ҳ<EFBFBD><EFBFBD><EFBFBD>Թ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݣ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ǲ<EFBFBD><EFBFBD>ڷ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>˽<EFBFBD><EFBFBD>й<EFBFBD><EFBFBD>˵<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݷǳ<EFBFBD><EFBFBD>󣬵<EFBFBD><EFBFBD><EFBFBD>ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>紫<EFBFBD><EFBFBD><EFBFBD>˺ܶ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݣ<EFBFBD><EFBFBD>Ӷ<EFBFBD><EFBFBD>˷<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+????<3F><>??????????????????????????????<3F><>?????????????????????<3F><>??????????????????????????????

 ```sql
 SELECT *
@ -112,155 +112,155 @@ FROM mytable
 WHERE col IS NULL;
 ```

-<EFBFBD>±<EFBFBD><EFBFBD><EFBFBD>ʾ<EFBFBD><EFBFBD> WHERE <20>Ӿ<EFBFBD><D3BE><EFBFBD><EFBFBD>õĲ<C3B5><C4B2><EFBFBD><EFBFBD><EFBFBD>
+?<3F><>?????? WHERE ????????????

-|  <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> | ˵<><CBB5>  |
+|  ?????? | ???  |
 | ------------ | ------------ |
-| = <  >  | <EFBFBD><EFBFBD><EFBFBD><EFBFBD> С<><D0A1> <20><><EFBFBD><EFBFBD> |
-| <> !=  | <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>  |
-| <= !> | С<EFBFBD>ڵ<EFBFBD><EFBFBD><EFBFBD> |
-| >= !< | <EFBFBD><EFBFBD><EFBFBD>ڵ<EFBFBD><EFBFBD><EFBFBD> |
-| BETWEEN | <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ֮<EFBFBD><EFBFBD> |
-| IS NULL | ΪNULLֵ |
+| = <  >  | ???? <20><>?? ???? |
+| <> !=  | ??????  |
+| <= !> | <20><>????? |
+| >= !< | ??????? |
+| BETWEEN | ?????????? |
+| IS NULL | ?NULL? |

-Ӧ<EFBFBD><EFBFBD>ע<EFBFBD>⵽<EFBFBD><EFBFBD>NULL <EFBFBD><EFBFBD> 0 <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD><EFBFBD>
+????????NULL ?? 0 ????????????????

-**AND OR** <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӷ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ȴ<EFBFBD><EFBFBD><EFBFBD> AND<4E><44><EFBFBD><EFBFBD><EFBFBD>˵<EFBFBD>һ<EFBFBD><D2BB><EFBFBD><EFBFBD><EFBFBD>˱<EFBFBD><CBB1><EFBFBD>ʽ<EFBFBD>漰<EFBFBD><E6BCB0><EFBFBD><EFBFBD><EFBFBD><EFBFBD> AND <EFBFBD><EFBFBD> OR ʱ<EFBFBD><EFBFBD>Ӧ<EFBFBD><EFBFBD>ʹ<EFBFBD><EFBFBD> () <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ȼ<EFBFBD><C8BC><EFBFBD>
+**AND OR** ??????????????????????????? AND?????????????????<3F>p????? AND ?? OR ????????? () ?????????????

-**IN** <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ƥ<EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD>ֵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҳ<EFBFBD><EFBFBD><EFBFBD>Խ<EFBFBD>һ<EFBFBD><EFBFBD> SELECT <20>Ӿ䣬<D3BE>Ӷ<EFBFBD>ƥ<EFBFBD><C6A5><EFBFBD>Ӳ<EFBFBD>ѯ<EFBFBD>õ<EFBFBD><C3B5><EFBFBD>һ<EFBFBD><D2BB>ֵ<EFBFBD><D6B5>
+**IN** ??????????????????????????????? SELECT ????????????????????????

-**NOT** <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڷ<EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+**NOT** ????????????????????

-# ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ????

-ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҳ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڹ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>У<EFBFBD>ֻ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ı<EFBFBD><EFBFBD>ֶΡ<EFBFBD>
+??????????????????<3F><>?????????????<3F><>?

- **%** ƥ<EFBFBD><EFBFBD> >=0 <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> \*<EFBFBD><EFBFBD>
+- **%** ??? >=0 ????????????????? \*??

- **\_** ƥ<EFBFBD><EFBFBD> ==1 <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> \.<EFBFBD><EFBFBD>
+- **\_** ??? ==1 ????????????????? \.??

- **[ ]** <EFBFBD><EFBFBD><EFBFBD><EFBFBD>ƥ<EFBFBD>伯<EFBFBD><EFBFBD><EFBFBD>ڵ<EFBFBD><EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD> ^ <20><><EFBFBD>Զ<EFBFBD><D4B6><EFBFBD><EFBFBD><EFBFBD><EFBFBD>з<EFBFBD><EFBFBD><EFBFBD>
+- **[ ]** ??????<3F><>????????????????? ^ ?????????<EFBFBD><EFBFBD>?

-ʹ<EFBFBD><EFBFBD> Like <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ƥ<EFBFBD>䡣
+??? Like ?????????????

 ```sql
 SELECT *
 FROM mytable
-WHERE col LIKE '[^AB]%' -- <EFBFBD><EFBFBD><EFBFBD><EFBFBD>AB<EFBFBD><EFBFBD>ͷ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ı<EFBFBD>
+WHERE col LIKE '[^AB]%' -- ????AB????????????
 ```

-<EFBFBD><EFBFBD>Ҫ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>λ<EFBFBD>ڿ<EFBFBD>ͷ<EFBFBD><EFBFBD>ƥ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ǳ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+?????????????????<3F><>????????????????

-# <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֶ<EFBFBD>
+# ???????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݿ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݵ<EFBFBD>ת<EFBFBD><EFBFBD><EFBFBD>͸<EFBFBD>ʽ<EFBFBD><EFBFBD><EFBFBD>Ĺ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ȿͻ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ͽ<EFBFBD><EFBFBD>ö࣬<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ת<EFBFBD><EFBFBD><EFBFBD>͸<EFBFBD>ʽ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ٵĻ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Լ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+?????????????????????????????????????????????????????????????????????????????????????????????????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֶ<EFBFBD>ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫʹ<EFBFBD><EFBFBD> **AS** <20><>ȡ<EFBFBD><C8A1><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD><CAB1><EFBFBD>ֶ<EFBFBD><D6B6><EFBFBD>Ϊ<EFBFBD><CEAA><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʽ<EFBFBD><CABD>
+???????????????? **AS** ????????????????????????????????????

 ```sql
 SELECT col1*col2 AS alias
 FROM mytable
 ```

-**Concat()** <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֶΡ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݿ<EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD>ÿո<EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD>ֵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ<EFBFBD>п<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ӵĽ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һЩ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫ<EFBFBD>Ŀո<EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD><EFBFBD> **TRIM()** <20><><EFBFBD><EFBFBD>ȥ<EFBFBD><C8A5><EFBFBD><EFBFBD>β<EFBFBD>ո<EFBFBD><D5B8><EFBFBD>
+**Concat()** ??????????????<3F><>?????????????????????????<3F><>?????????????????<3F><>???????????? **TRIM()** ?????????<3F><>???

 ```sql
 SELECT Concat(TRIM(col1), ' (', TRIM(col2), ')')
 FROM mytable
 ```

-# <EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD> DBMS <EFBFBD>ĺ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ǲ<EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD>ģ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>˲<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֲ<EFBFBD><EFBFBD>
+???? DBMS ???????????????????????????

-## <EFBFBD>ı<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+## ???????

-| <EFBFBD><EFBFBD><EFBFBD><EFBFBD>  | ˵<EFBFBD><EFBFBD>  |
+| ????  | ???  |
 | ------------ | ------------ |
-|  LEFT() RIGHT() |  <EFBFBD><EFBFBD><EFBFBD>߻<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ұߵ<EFBFBD><EFBFBD>ַ<EFBFBD> |
-|  LOWER() UPPER() |  ת<EFBFBD><EFBFBD>ΪСд<EFBFBD><EFBFBD><EFBFBD>ߴ<EFBFBD>д |
-| LTRIM() RTIM() | ȥ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>߻<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ұߵĿո<EFBFBD> |
-| LENGTH() | <EFBFBD><EFBFBD><EFBFBD><EFBFBD> |
-| SUNDEX() | ת<EFBFBD><EFBFBD>Ϊ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ |
+|  LEFT() RIGHT() |  ????????????? |
+|  LOWER() UPPER() |  ????<3F><><EFBFBD><EFBFBD>?????<3F><> |
+| LTRIM() RTIM() | ??????????????? |
+| LENGTH() | ???? |
+| SUNDEX() | ????????? |

-<EFBFBD><EFBFBD><EFBFBD>У<EFBFBD>**SOUNDEX()** <EFBFBD>ǽ<EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD>ת<EFBFBD><EFBFBD>Ϊ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʾ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĸ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ģʽ<EFBFBD><EFBFBD><EFBFBD>㷨<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ǹ<EFBFBD><EFBFBD>ݷ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĸ<EFBFBD>Ƚϡ<EFBFBD>
+???<3F><>?**SOUNDEX()** ????????????????????????????????????????????????????????????????????

 ```sql
 SELECT *
 FROM mytable
 WHERE SOUNDEX(col1) = SOUNDEX('apple')
 ```
-## <EFBFBD><EFBFBD><EFBFBD>ں<EFBFBD>ʱ<EFBFBD>䴦<EFBFBD><EFBFBD>
+## ??????????

-<EFBFBD><EFBFBD><EFBFBD>ڸ<EFBFBD>ʽ<EFBFBD><EFBFBD>YYYY-MM-DD
+????????YYYY-MM-DD

-ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʽ<EFBFBD><EFBFBD>HH:MM:SS
+???????HH:MM:SS

-|<EFBFBD><EFBFBD> <20><> | ˵ <20><>|
+|?? ?? | ? ??|
 | --- | --- |
-| AddDate() | <EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڣ<EFBFBD><EFBFBD>졢<EFBFBD>ܵȣ<EFBFBD>|
-| AddTime() | <EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD>ʱ<EFBFBD>䣨ʱ<EFBFBD><EFBFBD><EFBFBD>ֵȣ<EFBFBD>|
-| CurDate() | <EFBFBD><EFBFBD><EFBFBD>ص<EFBFBD>ǰ<EFBFBD><EFBFBD><EFBFBD><EFBFBD> |
-| CurTime() | <EFBFBD><EFBFBD><EFBFBD>ص<EFBFBD>ǰʱ<EFBFBD><EFBFBD> |
-|Date() |<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڲ<EFBFBD><EFBFBD><EFBFBD>|
-|DateDiff() |<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>֮<EFBFBD><EFBFBD>|
-|Date_Add() |<EFBFBD>߶<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>㺯<EFBFBD><EFBFBD>|
-|Date_Format() |<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʽ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڻ<EFBFBD>ʱ<EFBFBD>䴮|
-|Day()| <EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>|
-|DayOfWeek() |<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڣ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ض<EFBFBD>Ӧ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڼ<EFBFBD>|
-|Hour() |<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Сʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>|
-|Minute() |<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD>ķ<EFBFBD><EFBFBD>Ӳ<EFBFBD><EFBFBD><EFBFBD>|
-|Month() |<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڵ<EFBFBD><EFBFBD>·ݲ<EFBFBD><EFBFBD><EFBFBD>|
-|Now() |<EFBFBD><EFBFBD><EFBFBD>ص<EFBFBD>ǰ<EFBFBD><EFBFBD><EFBFBD>ں<EFBFBD>ʱ<EFBFBD><EFBFBD>|
-|Second() |<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>벿<EFBFBD><EFBFBD>|
-|Time() |<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD>䲿<EFBFBD><EFBFBD>|
-|Year() |<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݲ<EFBFBD><EFBFBD><EFBFBD>|
+| AddDate() | ??????????????????|
+| AddTime() | ?????????????????|
+| CurDate() | ?????????? |
+| CurTime() | ????????? |
+|Date() |???????????????????|
+|DateDiff() |???????????????|
+|Date_Add() |?????????????????|
+|Date_Format() |??????????????????????|
+|Day()| ????????????????????|
+|DayOfWeek() |?????????????????????????|
+|Hour() |???????????<3F><>?????|
+|Minute() |?????????????????|
+|Month() |?????????????<3F><>????|
+|Now() |??????????????|
+|Second() |???????????????|
+|Time() |????????????????????|
+|Year() |??????????????????|

 ```sql
 mysql> SELECT NOW();
        -> '2017-06-28 14:01:52'
 ```

-## <EFBFBD><EFBFBD>ֵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+## ???????

-| <EFBFBD><EFBFBD><EFBFBD><EFBFBD> | ˵<><CBB5> |
+| ???? | ??? |
 | --- | --- |
-| SIN() | <EFBFBD><EFBFBD><EFBFBD><EFBFBD> |
-|COS() | <EFBFBD><EFBFBD><EFBFBD><EFBFBD> |
-| TAN() | <EFBFBD><EFBFBD><EFBFBD><EFBFBD> |
-| ABS() | <EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ |
-| SQRT() | ƽ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>|
-| MOD() | <EFBFBD><EFBFBD><EFBFBD><EFBFBD>|
-| EXP() | ָ<EFBFBD><EFBFBD>|
-| PI() | Բ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>|
-|RAND() | <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>|
+| SIN() | ???? |
+|COS() | ???? |
+| TAN() | ???? |
+| ABS() | ????? |
+| SQRT() | ?????|
+| MOD() | ????|
+| EXP() | ???|
+| PI() | ?????|
+|RAND() | ?????|

-## <EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+## ????

-|<EFBFBD><EFBFBD> <20><> |˵ <20><>|
+|?? ?? |? ??|
 | --- | --- |
-|AVG() |<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĳ<EFBFBD>е<EFBFBD>ƽ<EFBFBD><EFBFBD>ֵ|
-|COUNT()| <EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĳ<EFBFBD>е<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>|
-|MAX()| <EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĳ<EFBFBD>е<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ|
-|MIN()| <EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĳ<EFBFBD>е<EFBFBD><EFBFBD><EFBFBD>Сֵ|
-|SUM() |<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĳ<EFBFBD><EFBFBD>ֵ֮<EFBFBD><EFBFBD>|
+|AVG() |??????<3F><>?????|
+|COUNT()| ??????<3F><>?????|
+|MAX()| ??????<3F><>?????|
+|MIN()| ??????<3F><>???<3F><>?|
+|SUM() |???????????|

-AVG() <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> NULL <EFBFBD>С<EFBFBD>
+AVG() ????? NULL ?<3F><>?

-DISTINCT <EFBFBD>ؼ<EFBFBD><EFBFBD>ֻ<EFBFBD>ֻ<EFBFBD><EFBFBD><EFBFBD>ܲ<EFBFBD>ͬ<EFBFBD><EFBFBD>ֵ<EFBFBD><EFBFBD>
+DISTINCT ??????????????????

 ```sql
 SELECT AVG(DISTINCT col1) AS avg_col
 FROM mytable
 ```

-# <EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ǰ<EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݷ<EFBFBD><EFBFBD><EFBFBD>ͬһ<EFBFBD><EFBFBD><EFBFBD>С<EFBFBD>
+?????????????????????????<3F><>?

-<EFBFBD><EFBFBD><EFBFBD>Զ<EFBFBD>ÿ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD>û<EFBFBD><EFBFBD>ܺ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>д<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ÿ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ƽ<EFBFBD><EFBFBD>ֵ<EFBFBD>ȡ<EFBFBD>
+????????????????????????<3F><>???????????????????????

-<EFBFBD><EFBFBD> col <EFBFBD><EFBFBD><EFBFBD>򲢷<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݣ<EFBFBD>
+?? col ????????????

 ```sql
 SELECT col, COUNT(*) AS num
@ -268,7 +268,7 @@ FROM mytable
 GROUP BY col;
 ```

-WHERE <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>У<EFBFBD>HAVING <20><><EFBFBD>˷<EFBFBD><CBB7>飬<EFBFBD>й<EFBFBD><D0B9><EFBFBD>Ӧ<EFBFBD><D3A6><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ˣ<EFBFBD>
+WHERE ?????<3F><>?HAVING ??????<3F><>?<3F><>?????????????????

 ```sql
 SELECT col, COUNT(*) AS num
@ -278,7 +278,7 @@ GROUP BY col
 HAVING COUNT(*) >= 2;
 ```

-GROUP BY <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֶΣ<EFBFBD><EFBFBD><EFBFBD> ORDER BY Ҳ<><D2B2><EFBFBD><EFBFBD><EFBFBD>Ծۼ<D4BE><DBBC>ֶ<EFBFBD><D6B6><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+GROUP BY ???????????????<3F><>??? ORDER BY ??????????????????????

 ```sql
 SELECT col, COUNT(*) AS num
@ -287,18 +287,18 @@ GROUP BY col
 ORDER BY num;
 ```

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>涨<EFBFBD><EFBFBD>
+????<3F><>??

-1. GROUP BY <EFBFBD>Ӿ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> WHERE <20>Ӿ<EFBFBD>֮<EFBFBD><D6AE><EFBFBD><EFBFBD>ORDER BY <EFBFBD>Ӿ<EFBFBD>֮ǰ<EFBFBD><EFBFBD>
-2. <EFBFBD><EFBFBD><EFBFBD>˻<EFBFBD><EFBFBD>ܼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>֮<EFBFBD>⣬SELECT <20><><EFBFBD><EFBFBD><EFBFBD>е<EFBFBD>ÿһ<C3BF>ж<EFBFBD><D0B6><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> GROUP BY <20>Ӿ<EFBFBD><D3BE>и<EFBFBD><D0B8><EFBFBD><EFBFBD><EFBFBD>
-3. NULL <EFBFBD><EFBFBD><EFBFBD>лᵥ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊһ<EFBFBD>飻
-4. <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> SQL ʵ<>ֲ<EFBFBD>֧<EFBFBD><D6A7> GROUP BY <20>о<EFBFBD><D0BE>пɱ䳤<C9B1>ȵ<EFBFBD><C8B5><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>͡<EFBFBD>
+1. GROUP BY ???????? WHERE ??????ORDER BY ???????
+2. ????????????????SELECT ????<3F><>????<3F><>??????? GROUP BY ????<3F><>?????
+3. NULL ???<3F><>????????<3F><>
+4. ????? SQL ??????? GROUP BY ?<3F><>??<3F><>??????????????

-# <EFBFBD>Ӳ<EFBFBD>ѯ
+# ????

-<EFBFBD>Ӳ<EFBFBD>ѯ<EFBFBD><EFBFBD>ֻ<EFBFBD>ܷ<EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD>С<EFBFBD>
+????????????????<3F><>?

-<EFBFBD><EFBFBD><EFBFBD>Խ<EFBFBD><EFBFBD>Ӳ<EFBFBD>ѯ<EFBFBD>Ľ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ WHRER <20><><EFBFBD><EFBFBD><EFBFBD>Ĺ<EFBFBD><C4B9><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+???????????????? WHRER ?????????????

 ```
 SELECT *
@ -307,7 +307,7 @@ WHERE col1 IN (SELECT col2
                 FROM mytable2);
 ```

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Լ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͻ<EFBFBD><EFBFBD>Ķ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӳ<EFBFBD>ѯ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Լ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ÿ<EFBFBD><EFBFBD><EFBFBD>ͻ<EFBFBD>ִ<EFBFBD><EFBFBD>һ<EFBFBD>Σ<EFBFBD>
+?????????????????????????????????????????????????????????<3F><>?

 ```sql
 SELECT cust_name, (SELECT COUNT(*)
@ -318,17 +318,17 @@ FROM Customers
 ORDER BY cust_name;
 ```

-# <EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӷ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD><EFBFBD> JOIN <20>ؼ<EFBFBD><D8BC>֣<EFBFBD><D6A3><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD><CAB9> ON<EFBFBD><EFBFBD>
+??????????????????? JOIN ???????????????????? ON??

-<EFBFBD><EFBFBD><EFBFBD>ӿ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>滻<EFBFBD>Ӳ<EFBFBD>ѯ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ұ<EFBFBD><EFBFBD>Ӳ<EFBFBD>ѯ<EFBFBD><EFBFBD>Ч<EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>졣
+????????<3F>I?????????????????<3F><>?????????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> AS <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֶκͱ<CEBA><CDB1><EFBFBD>ȡ<EFBFBD><C8A1><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ȡ<EFBFBD><C8A1><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ<EFBFBD>˼<EFBFBD><CBBC><EFBFBD> SQL <20><><EFBFBD><EFBFBD><EFBFBD>Լ<EFBFBD><D4BC><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD><CDAC><EFBFBD><EFBFBD>
+?????? AS ??????????????<3F><>???????????????????????????? SQL ???????????????

-## <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+## ??????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֳƵ<EFBFBD>ֵ<EFBFBD><EFBFBD><EFBFBD>ӣ<EFBFBD>ʹ<EFBFBD><EFBFBD> INNER JOIN <EFBFBD>ؼ<EFBFBD><EFBFBD>֡<EFBFBD>
+??????????????????? INNER JOIN ??????

 ```
 select a, b, c
@ -336,7 +336,7 @@ from A inner join B
 on A.key = B.key
 ```

-<EFBFBD><EFBFBD><EFBFBD>Բ<EFBFBD><EFBFBD><EFBFBD>ȷʹ<EFBFBD><EFBFBD> INNER JOIN<49><4E><EFBFBD><EFBFBD>ʹ<EFBFBD><CAB9><EFBFBD><EFBFBD>ͨ<EFBFBD><CDA8>ѯ<EFBFBD><D1AF><EFBFBD><EFBFBD> WHERE <20>н<EFBFBD><D0BD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫ<EFBFBD><D2AA><EFBFBD>ӵ<EFBFBD><D3B5><EFBFBD><EFBFBD>õ<EFBFBD>ֵ<EFBFBD><D6B5><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+??????????? INNER JOIN????????????????? WHERE ?<3F><>???????????????????????????????????

 ```
 select a, b, c
@ -344,15 +344,15 @@ from A, B
 where A.key = B.key
 ```

-<EFBFBD><EFBFBD>û<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>·<EFBFBD><EFBFBD>صѿ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+?????????????????<3F><>???????????

-## <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+## ??????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ӿ<EFBFBD><EFBFBD>Կ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ӵ<EFBFBD>һ<EFBFBD>֣<EFBFBD>ֻ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ӵı<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ѡ<EFBFBD>
+??????????????????????????????????????????

-һ<EFBFBD><EFBFBD>Ա<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ա<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ա<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ţ<EFBFBD>Ҫ<EFBFBD>ҳ<EFBFBD><EFBFBD><EFBFBD> Jim <20><><EFBFBD><EFBFBD>ͬһ<CDAC><D2BB><EFBFBD>ŵ<EFBFBD><C5B5><EFBFBD><EFBFBD><EFBFBD>Ա<EFBFBD><D4B1><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+??????????????????????????????????????? Jim ????????????????????????

-**<EFBFBD>Ӳ<EFBFBD>ѯ<EFBFBD>汾**
+**?????<3F><EFBFBD>**

 ```
 select name
@ -363,7 +363,7 @@ where department = (
      where name = "Jim");
 ```

-**<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӱ汾**
+**??????<EFBFBD><EFBFBD>**

 ```
 select name
@ -372,24 +372,24 @@ where e1.department = e2.department
      and e1.name = "Jim";
 ```

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӳ<EFBFBD>ѯ<EFBFBD><EFBFBD>Ч<EFBFBD>ʸߡ<EFBFBD>
+??????????????<3F><>????

-## <EFBFBD><EFBFBD>Ȼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+## ???????

-<EFBFBD><EFBFBD>Ȼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ǰ<EFBFBD>ͬ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ģ<EFBFBD>ͬ<EFBFBD><EFBFBD><EFBFBD>п<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ж<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+????????????????????????????????????????<3F><>????<3F><>????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӻ<EFBFBD><EFBFBD><EFBFBD>Ȼ<EFBFBD><EFBFBD><EFBFBD>ӵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ṩ<EFBFBD><EFBFBD><EFBFBD>ӵ<EFBFBD><EFBFBD>У<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ȼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Զ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD><EFBFBD><EFBFBD>У<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ȼ<EFBFBD><EFBFBD><EFBFBD>ӡ<EFBFBD>
+?????????????????????????????????<3F><>?????????????????????????<3F><>???????????????????

 ```
 select *
 from employee natural join department;
 ```

-## <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+## ??????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ӱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>û<EFBFBD>й<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Щ<EFBFBD>С<EFBFBD><EFBFBD><EFBFBD>Ϊ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ӣ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Լ<EFBFBD>ȫ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ӣ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӿ<EFBFBD><EFBFBD>Ǳ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>С<EFBFBD>
+?????????????<3F><>???????<EFBFBD><EFBFBD>?<EFBFBD><EFBFBD>???????????????????????????????????????????????????????<3F><>?

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>й˿͵Ķ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϣ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>û<EFBFBD>ж<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϣ<EFBFBD>Ĺ˿͡<EFBFBD>
+???????<3F><>???????????????????<3F><>???????????

 ```
 select Customers.cust_id, Orders.order_num
@ -397,7 +397,7 @@ select Customers.cust_id, Orders.order_num
   on Customers.cust_id = Orders.curt_id
 ```

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫͳ<EFBFBD>ƹ˿͵Ķ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD>þۼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+??????????????????????????????

 ```
 select Customers.cust_id,
@ -407,13 +407,13 @@ on Customers.cust_id = Orders.curt_id
 group by Customers.cust_id
 ```

-# <EFBFBD><EFBFBD><EFBFBD>ϲ<EFBFBD>ѯ
+# ?????

-ʹ<EFBFBD><EFBFBD> **UNION** <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ѯ<EFBFBD><EFBFBD>ÿ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ѯ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD><EFBFBD><EFBFBD>С<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʽ<EFBFBD><EFBFBD><EFBFBD>߾ۼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+??? **UNION** ??????????????????????????????????<3F><>?????????????????

-Ĭ<EFBFBD>ϻ<EFBFBD>ȥ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD>У<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD>У<EFBFBD>ʹ<EFBFBD><EFBFBD> UNION ALL <EFBFBD><EFBFBD>
+???????????<3F><>???????????????<3F><>???? UNION ALL ??

-ֻ<EFBFBD>ܰ<EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD> ORDER BY <EFBFBD>Ӿ䣬<EFBFBD><EFBFBD><EFBFBD>ұ<EFBFBD><EFBFBD><EFBFBD>λ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+????????? ORDER BY ??????????<3F><>?????????

 ```sql
 SELECT col
@ -425,16 +425,16 @@ FROM mytable
 WHERE col =2;
 ```

-# <EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ????

-**<EFBFBD><EFBFBD>ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>**
+**???????**

 ```sql
 INSERT INTO mytable(col1, col2)
 VALUES(val1, val2);
 ```

-**<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>**
+**?????????????????**

 ```sql
 INSERT INTO mytable1(col1, col2)
@ -442,14 +442,14 @@ SELECT col1, col2
 FROM mytable2;
 ```

-**<EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݸ<EFBFBD><EFBFBD>Ƶ<EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD>±<EFBFBD>**
+**????????????????????<3F><>?**

 ```sql
 CREATE TABLE newtable AS
 SELECT * FROM mytable;
 ```

-# <EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ????

 ```sql
 UPDATE mytable
@ -457,18 +457,18 @@ SET col = val
 WHERE id = 1;
 ```

-# ɾ<EFBFBD><EFBFBD>
+# ???

 ```sql
 DELETE FROM mytable
 WHERE id = 1;
 ```

-**TRUNCATE TABLE** <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ձ<EFBFBD><EFBFBD><EFBFBD>Ҳ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ɾ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>С<EFBFBD>
+**TRUNCATE TABLE** ?????????????????????<3F><>?

-ʹ<EFBFBD>ø<EFBFBD><EFBFBD>º<EFBFBD>ɾ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱһ<EFBFBD><EFBFBD>Ҫ<EFBFBD><EFBFBD> WHERE <20>Ӿ䣬<D3BE><E4A3AC>Ȼ<EFBFBD><C8BB><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ű<EFBFBD><C5B1><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݶ<EFBFBD><DDB6>ƻ<EFBFBD><C6BB><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> SELECT <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>в<EFBFBD><D0B2>ԣ<EFBFBD><D4A3><EFBFBD>ֹ<EFBFBD><D6B9><EFBFBD><EFBFBD>ɾ<EFBFBD><C9BE><EFBFBD><EFBFBD>
+????????????????????? WHERE ????????????????????????????????? SELECT ?????<3F><>????????????????

-# <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ??????

 ```sql
 CREATE TABLE mytable (
@ -479,38 +479,38 @@ CREATE TABLE mytable (
  PRIMARY KEY (`id`));
 ```

-# <EFBFBD>޸ı<EFBFBD>
+# ????

-**<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>**
+**?????**

 ```sql
 ALTER TABLE mytable
 ADD col CHAR(20);
 ```

-**ɾ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>**
+**?????**

 ```sql
 ALTER TABLE mytable
 DROP COLUMN col;
 ```

-**ɾ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>**
+**?????**

 ```sql
 DROP TABLE mytable;
 ```

-# <EFBFBD><EFBFBD>ͼ
+# ???

-<EFBFBD><EFBFBD>ͼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ı<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݣ<EFBFBD>Ҳ<EFBFBD>Ͳ<EFBFBD><EFBFBD>ܶ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͼ<EFBFBD>Ĳ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ͷ<EFBFBD><EFBFBD><EFBFBD>ͨ<EFBFBD><EFBFBD><EFBFBD>Ĳ<EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+?????????????????????????????????????????????????????????????????????????

-<EFBFBD><EFBFBD>ͼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ºô<EFBFBD><EFBFBD><EFBFBD>
+???????????????

-1. <EFBFBD>򻯸<EFBFBD><EFBFBD>ӵ<EFBFBD> SQL <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>縴<EFBFBD>ӵ<EFBFBD><D3B5><EFBFBD><EFBFBD>᣻
-2. ֻʹ<EFBFBD><EFBFBD>ʵ<EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݣ<EFBFBD>
-3. ͨ<EFBFBD><EFBFBD>ֻ<EFBFBD><EFBFBD><EFBFBD>û<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͼ<EFBFBD><EFBFBD>Ȩ<EFBFBD>ޣ<EFBFBD><EFBFBD><EFBFBD>֤<EFBFBD><EFBFBD><EFBFBD>ݵİ<EFBFBD>ȫ<EFBFBD>ԣ<EFBFBD>
-4. <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݸ<EFBFBD>ʽ<EFBFBD>ͱ<EFBFBD>ʾ<EFBFBD><EFBFBD>
+1. ?????? SQL ?????????<3F>y???????
+2. ???????????????????
+3. ???????????????????????????????????
+4. ????????????????

 ```sql
 CREATE VIEW myview AS
@ -519,25 +519,25 @@ FROM mytable
 WHERE col5 = val;
 ```

-# <EFBFBD>洢<EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ?<3F><>????

-<EFBFBD>洢<EFBFBD><EFBFBD><EFBFBD>̿<EFBFBD><EFBFBD>Կ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ƕ<EFBFBD>һϵ<EFBFBD><EFBFBD> SQL <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+?<3F><>????????????????? SQL ????????????

-**ʹ<EFBFBD>ô洢<EFBFBD><EFBFBD><EFBFBD>̵ĺô<EFBFBD>**
+**???<3F><>???????**

-1. <EFBFBD><EFBFBD>ʵ<EFBFBD>ַ<EFBFBD>װ<EFBFBD><EFBFBD><EFBFBD>˴洢<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>У<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>򵥣<EFBFBD>Ҳ<EFBFBD><EFBFBD>֤<EFBFBD>˰<EFBFBD>ȫ<EFBFBD>ԣ<EFBFBD>
-2. <EFBFBD><EFBFBD><EFBFBD>Ը<EFBFBD><EFBFBD>ô<EFBFBD><EFBFBD>룻
-3. <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ԥ<EFBFBD>ȱ<EFBFBD><EFBFBD>룬<EFBFBD><EFBFBD><EFBFBD>˾<EFBFBD><EFBFBD>кܸߵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ܡ<EFBFBD>
+1. ???????????<3F><>?????<3F><>???????????????????
+2. ??????????
+3. ?????????????????<3F><>????????

-**<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>洢<EFBFBD><EFBFBD><EFBFBD><EFBFBD>**
+**?????<3F><>????**

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>д<EFBFBD><EFBFBD><EFBFBD><EFBFBD>洢<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫ<EFBFBD>Զ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ָ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> ; Ϊ<><CEAA><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>洢<EFBFBD><E6B4A2><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҳ<EFBFBD><D2B2><EFBFBD><EFBFBD><EFBFBD>˷ֺţ<D6BA><C5A3><EFBFBD><EFBFBD>˻<EFBFBD><CBBB><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ⲿ<EFBFBD>ַֺŵ<D6BA><C5B5><EFBFBD><EFBFBD>ǽ<EFBFBD><C7BD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>﷨<EFBFBD><EFB7A8><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+???????<3F><>????<3F><>??????????????????????????????? ; ????????????<3F><>???????????????????????????????????????????????????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD> in<EFBFBD><EFBFBD>out <EFBFBD><EFBFBD> inout <EFBFBD><EFBFBD><EFBFBD>ֲ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+???? in??out ?? inout ?????????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫ<EFBFBD><EFBFBD> select into <EFBFBD><EFBFBD><EFBFBD>䡣
+???????????????? select into ???

-ÿ<EFBFBD><EFBFBD>ֻ<EFBFBD>ܸ<EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>֧<EFBFBD>ּ<EFBFBD><EFBFBD>ϵĲ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+?????????????????????????????????

 ```sql
 delimiter //
@ -558,18 +558,18 @@ call myprocedure(@ret);
 select @ret;
 ```

-# <EFBFBD>α<EFBFBD>
+# ?<3F><>?

-<EFBFBD>ڴ洢<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD><EFBFBD><EFBFBD>α<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Զ<EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ƶ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+??<3F><>??????????<3F><>??????????????????????????

-<EFBFBD>α<EFBFBD><EFBFBD><EFBFBD>Ҫ<EFBFBD><EFBFBD><EFBFBD>ڽ<EFBFBD><EFBFBD><EFBFBD>ʽӦ<EFBFBD>ã<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>û<EFBFBD><EFBFBD><EFBFBD>Ҫ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݼ<EFBFBD><EFBFBD>е<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>н<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>޸ġ<EFBFBD>
+?<3F><>??????????????????????????????????<3F><>??????<3F><>????????????

-**ʹ<EFBFBD><EFBFBD><EFBFBD>α<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĸ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>裺**
+**????<3F><>????????<3F>s**

-1. <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>α꣬<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>û<EFBFBD><EFBFBD>ʵ<EFBFBD>ʼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݣ<EFBFBD>
-2. <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>αꣻ
-3. ȡ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݣ<EFBFBD>
-4. <EFBFBD>ر<EFBFBD><EFBFBD>αꣻ
+1. ?????<3F><>????????????????????????
+2. ???<3F><>?
+3. ????????
+4. ????<3F><>?

 ```sql
 delimiter //
@ -579,7 +579,7 @@ create procedure myprocedure(out ret int)

        declare mycursor cursor for
        select col1 from mytable;
-        # <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD>continue handler<EFBFBD><EFBFBD><EFBFBD><EFBFBD> sqlstate '02000' <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ִ<EFBFBD><EFBFBD> set done = 1
+        # ?????????continue handler???? sqlstate '02000' ??????????????????? set done = 1
        declare continue handler for sqlstate '02000' set done = 1;

        open mycursor;
@ -594,43 +594,43 @@ create procedure myprocedure(out ret int)
 delimiter ;
 ```

-# <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ??????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĳ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ִ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD>Զ<EFBFBD>ִ<EFBFBD>У<EFBFBD>DELETE<EFBFBD><EFBFBD>INSERT<EFBFBD><EFBFBD>UPDATE
+?????????????????????????????????<3F><>?DELETE??INSERT??UPDATE

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ָ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ִ<EFBFBD><EFBFBD>֮ǰ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>֮<EFBFBD><EFBFBD><EFBFBD>Զ<EFBFBD>ִ<EFBFBD>У<EFBFBD>֮ǰִ<EFBFBD><EFBFBD>ʹ<EFBFBD><EFBFBD> BEFORE <20>ؼ<EFBFBD><D8BC>֣<EFBFBD>֮<EFBFBD><D6AE>ִ<EFBFBD><D6B4>ʹ<EFBFBD><CAB9> AFTER <EFBFBD>ؼ<EFBFBD><EFBFBD>֡<EFBFBD>BEFORE <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>֤<EFBFBD>;<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+???????????????????????????????????<3F><>????????? BEFORE ??????????????? AFTER ??????BEFORE ??????????????????

-INSERT <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ NEW <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+INSERT ???????????????? NEW ???????

 ```sql
 CREATE TRIGGER mytrigger AFTER INSERT ON mytable
 FOR EACH ROW SELECT NEW.col;
 ```

-DELETE <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ OLD <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֻ<EFBFBD><D6BB><EFBFBD>ġ<EFBFBD>
+DELETE ???????????????? OLD ???????????????????

-UPDATE <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ NEW <20><>һ<EFBFBD><D2BB><EFBFBD><EFBFBD>Ϊ OLD <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> NEW <20>ǿ<EFBFBD><C7BF>Ա<EFBFBD><D4B1>޸ĵأ<C4B5><D8A3><EFBFBD> OLD <20><>ֻ<EFBFBD><D6BB><EFBFBD>ġ<EFBFBD>
+UPDATE ???????????????? NEW ???????? OLD ??????????? NEW ????????????? OLD ????????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD>ô<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ƹ<EFBFBD><EFBFBD>٣<EFBFBD><EFBFBD><EFBFBD><EFBFBD>޸ļ<EFBFBD>¼<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD>ű<EFBFBD><EFBFBD>С<EFBFBD>
+???????????????????????????????????????????<3F><>?

-MySQL <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڴ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD><EFBFBD> CALL <20><><EFBFBD><EFBFBD> <20><>Ҳ<EFBFBD><D2B2><EFBFBD>ǲ<EFBFBD><C7B2>ܵ<EFBFBD><DCB5>ô洢<C3B4><E6B4A2><EFBFBD>̡<EFBFBD>
+MySQL ?????????????????? CALL ??? ?????????????<3F><>?????

-# <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+# ??????

-**<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>**
+**????????**

-1. <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>transaction<EFBFBD><EFBFBD>ָһ<EFBFBD><EFBFBD> SQL <EFBFBD><EFBFBD><EFBFBD>䣻
-2. <EFBFBD><EFBFBD><EFBFBD>ˣ<EFBFBD>rollback<EFBFBD><EFBFBD>ָ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ָ<EFBFBD><EFBFBD> SQL <20><><EFBFBD><EFBFBD><EFBFBD>Ĺ<EFBFBD><C4B9>̣<EFBFBD>
-3. <EFBFBD>ύ<EFBFBD><EFBFBD>commit<EFBFBD><EFBFBD>ָ<EFBFBD><EFBFBD>δ<EFBFBD>洢<EFBFBD><EFBFBD> SQL <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>д<EFBFBD><D0B4><EFBFBD><EFBFBD><EFBFBD>ݿ<EFBFBD><DDBF><EFBFBD><EFBFBD><EFBFBD>
-4. <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>㣨savepoint<EFBFBD><EFBFBD>ָ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>õ<EFBFBD><EFBFBD><EFBFBD>ʱռλ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>placeholder<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Զ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ˣ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+1. ????transaction?????? SQL ???
+2. ?????rollback?????????? SQL ????????
+3. ????commit?????<EFBFBD><EFBFBD>?<EFBFBD><EFBFBD>?? SQL ?????<3F><>????????
+4. ??????savepoint????????????????????<3F><>????placeholder?????????????????????????????????????????

-<EFBFBD><EFBFBD><EFBFBD>ܻ<EFBFBD><EFBFBD><EFBFBD> SELECT <EFBFBD><EFBFBD><EFBFBD>䣬<EFBFBD><EFBFBD><EFBFBD><EFBFBD> SELECT <20><><EFBFBD><EFBFBD>Ҳû<D2B2><C3BB><EFBFBD>壻Ҳ<E5A3BB><D2B2><EFBFBD>ܻ<EFBFBD><DCBB><EFBFBD> CRETE <EFBFBD><EFBFBD> DROP <EFBFBD><EFBFBD><EFBFBD>䡣
+??????? SELECT ??????? SELECT ????????<3F><>???????? CRETE ?? DROP ???

-MySQL <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ύĬ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʽ<EFBFBD>ύ<EFBFBD><EFBFBD>Ҳ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ÿִ<EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͻ<EFBFBD><EFBFBD>ύһ<EFBFBD>Ρ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> START TRANSACTION <20><><EFBFBD><EFBFBD>ʱ<EFBFBD><CAB1><EFBFBD><EFBFBD><EFBFBD>ر<EFBFBD><D8B1><EFBFBD>ʽ<EFBFBD>ύ<EFBFBD><E1BDBB><EFBFBD><EFBFBD> COMMIT <EFBFBD><EFBFBD> ROLLBACK <EFBFBD><EFBFBD><EFBFBD><EFBFBD>ִ<EFBFBD>к<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Զ<EFBFBD><EFBFBD>رգ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>»ָ<EFBFBD><EFBFBD><EFBFBD>ʽ<EFBFBD>ύ<EFBFBD><EFBFBD>
+MySQL ?????????????????????????????????????????<3F><>??????? START TRANSACTION ??????????????????? COMMIT ?? ROLLBACK ?????<3F><>??????????????????????????

-ͨ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> autocommit Ϊ 0 <EFBFBD><EFBFBD><EFBFBD><EFBFBD>ȡ<EFBFBD><EFBFBD><EFBFBD>Զ<EFBFBD><EFBFBD>ύ<EFBFBD><EFBFBD>ֱ<EFBFBD><EFBFBD> autocommit <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ 1 <20>Ż<EFBFBD><C5BB>ύ<EFBFBD><E1BDBB>autocommit <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ÿ<EFBFBD><C3BF><EFBFBD><EFBFBD><EFBFBD>Ӷ<EFBFBD><D3B6><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Է<EFBFBD><D4B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ġ<EFBFBD>
+??????? autocommit ? 0 ????????????????? autocommit ??????? 1 ???????autocommit ???????????????????????????????

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD>û<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ñ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>㣬ROLLBACK <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>˵<EFBFBD> START TRANSACTION <EFBFBD><EFBFBD><EFBFBD>䴦<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>˱<EFBFBD><EFBFBD><EFBFBD><EFBFBD>㣬<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> ROLLBACK <20><>ָ<EFBFBD><D6B8><EFBFBD>ñ<EFBFBD><C3B1><EFBFBD><EFBFBD>㣬<EFBFBD><E3A3AC><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>˵<EFBFBD><CBB5>ñ<EFBFBD><C3B1><EFBFBD><EFBFBD>㡣
+???????????????ROLLBACK ?????? START TRANSACTION ????????????????????????? ROLLBACK ??????????????????????????

 ```sql
 START TRANSACTION
@ -642,15 +642,15 @@ ROLLBACK TO delete1
 COMMIT
 ```

-# <EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD>
+# ?????

-**<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>**
+**????????**

-1. <EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD>Ϊ<EFBFBD><EFBFBD>ĸ<EFBFBD>ͷ<EFBFBD><EFBFBD>ŵļ<EFBFBD><EFBFBD>ϣ<EFBFBD>
-2. <EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊĳ<EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ա<EFBFBD><EFBFBD><EFBFBD>ڲ<EFBFBD><EFBFBD><EFBFBD>ʾ<EFBFBD><EFBFBD>
-3. У<EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD>ָ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>αȽϣ<EFBFBD><EFBFBD><EFBFBD>Ҫ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͷ<EFBFBD><EFBFBD>顣
+1. ???????????????????
+2. ??????????????????????????
+3. <20><>??????????<3F><>?????????????????<3F><>

-<EFBFBD><EFBFBD><EFBFBD>˸<EFBFBD><EFBFBD><EFBFBD>ָ<EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>У<EFBFBD><EFBFBD><EFBFBD>⣬Ҳ<EFBFBD><EFBFBD><EFBFBD>Ը<EFBFBD><EFBFBD><EFBFBD>ָ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+?????????????????<3F><>?????????????????

 ```sql
 CREATE TABLE mytable
@ -658,7 +658,7 @@ CREATE TABLE mytable
 DEFAULT CHARACTER SET hebrew COLLATE hebrew_general_ci;
 ```

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>򡢷<EFBFBD><EFBFBD><EFBFBD>ʱָ<EFBFBD><EFBFBD>У<EFBFBD>ԣ<EFBFBD>
+?????????????????<3F><>???

 ```sql
 SELECT *
@ -666,67 +666,67 @@ FROM mytable
 ORDER BY col COLLATE latin1_general_ci;
 ```

-# Ȩ<EFBFBD>޹<EFBFBD><EFBFBD><EFBFBD>
+# ??????

-MySQL <EFBFBD><EFBFBD><EFBFBD>˻<EFBFBD><EFBFBD><EFBFBD>Ϣ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> mysql <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݿ<EFBFBD><DDBF>С<EFBFBD>
+MySQL ?????????????? mysql ?????????<3F><>?

 ```sql
 USE mysql;
 SELECT user FROM user;
 ```

-**<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>˻<EFBFBD>**
+**???????**

 ```sql
 CREATE USER myuser IDENTIFIED BY 'mypassword';
 ```

-<EFBFBD>´<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>˻<EFBFBD>û<EFBFBD><EFBFBD><EFBFBD>κ<EFBFBD>Ȩ<EFBFBD>ޡ<EFBFBD>
+??????????????<3F><>?????

-**<EFBFBD>޸<EFBFBD><EFBFBD>˻<EFBFBD><EFBFBD><EFBFBD>**
+**????????**

 ```sql
 RENAME myuser TO newuser;
 ```

-**ɾ<EFBFBD><EFBFBD><EFBFBD>˻<EFBFBD>**
+**??????**

 ```sql
 DROP USER myuser;
 ```

-**<EFBFBD>鿴Ȩ<EFBFBD><EFBFBD>**
+**?????**

 ```sql
 SHOW GRANTS FOR myuser;
 ```
 ![](https://github.com/CyC2018/InterviewNotes/blob/master/pics/c73aa08e-a987-43c9-92be-adea4a884c25.png)

-<EFBFBD>˻<EFBFBD><EFBFBD><EFBFBD> username@host <20><><EFBFBD><EFBFBD>ʽ<EFBFBD><EFBFBD><EFBFBD>壬username@% ʹ<EFBFBD>õ<EFBFBD><EFBFBD><EFBFBD>Ĭ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+????? username@host ????????<EFBFBD><EFBFBD>username@% ?????????????????

-**<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ȩ<EFBFBD><EFBFBD>**
+**???????**

 ```sql
 GRANT SELECT, INSERT ON mydatabase.* TO myuser;
 ```

-**ɾ<EFBFBD><EFBFBD>Ȩ<EFBFBD><EFBFBD>**
+**??????**

 ```sql
 REVOKE SELECT, INSERT ON mydatabase.* FROM myuser;
 ```

-GRANT <EFBFBD><EFBFBD> REVOKE <EFBFBD><EFBFBD><EFBFBD>ڼ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ͽ<EFBFBD><EFBFBD>Ʒ<EFBFBD><EFBFBD><EFBFBD>Ȩ<EFBFBD>ޣ<EFBFBD>
+GRANT ?? REVOKE ??????????????????????

- <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD><EFBFBD> GRANT ALL<EFBFBD><EFBFBD> REVOKE ALL<EFBFBD><EFBFBD>
- <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݿ⣬ʹ<EFBFBD><EFBFBD> ON database.\*<EFBFBD><EFBFBD>
- <EFBFBD>ض<EFBFBD><EFBFBD>ı<EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD><EFBFBD> ON database.table<EFBFBD><EFBFBD>
- <EFBFBD>ض<EFBFBD><EFBFBD><EFBFBD><EFBFBD>У<EFBFBD>
- <EFBFBD>ض<EFBFBD><EFBFBD>Ĵ洢<EFBFBD><EFBFBD><EFBFBD>̡<EFBFBD>
+- ??????????????? GRANT ALL?? REVOKE ALL??
+- ???????????? ON database.\*??
+- ????????? ON database.table??
+- ??????<3F><>?
+- ?????<3F><>?????

-**<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>**
+**????????**

-<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD><EFBFBD> Password() <EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+??????? Password() ????

 ```sql
 SET PASSWROD FOR myuser = Password('newpassword');