update several sql statements (#2859) (#2877)

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

Author: ti-srebot

sql-statements/sql-statement-set-names.md

@@ -11,9 +11,33 @@ The statements `SET NAMES`, `SET CHARACTER SET` and `SET CHARSET` modify the var
 
 ## Synopsis
 
-**SetStmt:**
+**SetNamesStmt:**
 
-![SetStmt](/media/sqlgram/SetStmt.png)
+![SetNamesStmt](/media/sqlgram/SetNamesStmt.png)
+
+**VariableAssignmentList:**
+
+![VariableAssignmentList](/media/sqlgram/VariableAssignmentList.png)
+
+**VariableAssignment:**
+
+![VariableAssignment](/media/sqlgram/VariableAssignment.png)
+
+**CharsetName:**
+
+![CharsetName](/media/sqlgram/CharsetName.png)
+
+**StringName:**
+
+![StringName](/media/sqlgram/StringName.png)
+
+**CharsetKw:**
+
+![CharsetKw](/media/sqlgram/CharsetKw.png)
+
+**CharsetNameOrDefault:**
+
+![CharsetNameOrDefault](/media/sqlgram/CharsetNameOrDefault.png)
 
 ## Examples
 

sql-statements/sql-statement-show-columns-from.md

@@ -17,14 +17,42 @@ The statements `SHOW [FULL] FIELDS FROM`, `DESC <table>`, `DESCRIBE <table>` and
 
 ![ShowStmt](/media/sqlgram/ShowStmt.png)
 
-**ShowTargetFilterable:**
+**ShowColumnsFilterable:**
 
-![ShowTargetFilterable](/media/sqlgram/ShowTargetFilterable.png)
+![ShowColumnsFilterable](/media/sqlgram/ShowColumnsFilterable.png)
 
 **OptFull:**
 
 ![OptFull](/media/sqlgram/OptFull.png)
 
+**FieldsOrColumns:**
+
+![FieldsOrColumns](/media/sqlgram/FieldsOrColumns.png)
+
+**ShowTableAliasOpt:**
+
+![ShowTableAliasOpt](/media/sqlgram/ShowTableAliasOpt.png)
+
+**FromOrIn:**
+
+![FromOrIn](/media/sqlgram/FromOrIn.png)
+
+**TableName:**
+
+![TableName](/media/sqlgram/TableName.png)
+
+**ShowDatabaseNameOpt:**
+
+![ShowDatabaseNameOpt](/media/sqlgram/ShowDatabaseNameOpt.png)
+
+**DBName:**
+
+![DBName](/media/sqlgram/DBName.png)
+
+**ShowLikeOrWhereOpt:**
+
+![ShowLikeOrWhereOpt](/media/sqlgram/ShowLikeOrWhereOpt.png)
+
 ## Examples
 
 ```sql
@@ -85,7 +113,7 @@ mysql> show full columns from mysql.user;
 +-----------------------+---------------+-------------+------+------+---------+-------+---------------------------------+---------+
 | Host                  | char(64)      | utf8mb4_bin | NO   | PRI  | NULL    |       | select,insert,update,references |         |
 | User                  | char(32)      | utf8mb4_bin | NO   | PRI  | NULL    |       | select,insert,update,references |         |
-| Password              | char(41)      | utf8mb4_bin | YES  |      | NULL    |       | select,insert,update,references |         |
+| authentication_string | text          | utf8mb4_bin | YES  |      | NULL    |       | select,insert,update,references |         |
 | Select_priv           | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
 | Insert_priv           | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
 | Update_priv           | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
@@ -112,8 +140,12 @@ mysql> show full columns from mysql.user;
 | Create_role_priv      | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
 | Drop_role_priv        | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
 | Account_locked        | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
+| Shutdown_priv         | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
+| Reload_priv           | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
+| FILE_priv             | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
+| Config_priv           | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
 +-----------------------+---------------+-------------+------+------+---------+-------+---------------------------------+---------+
-29 rows in set (0.00 sec)
+33 rows in set (0.01 sec)
 ```
 
 ## MySQL compatibility

sql-statements/sql-statement-show-create-sequence.md

@@ -11,9 +11,9 @@ The `SHOW CREATE SEQUENCE` shows the detailed information of a sequence, which i
 
 ## Synopsis
 
-**ShowStmt:**
+**ShowCreateSequenceStmt:**
 
-![ShowStmt](/media/sqlgram/ShowStmt.png)
+![ShowCreateSequenceStmt](/media/sqlgram/ShowCreateSequenceStmt.png)
 
 **TableName:**