update sql-statement-show-table-next-rowid.md

TOC.md

@@ -280,6 +280,7 @@
       + [`SHOW [FULL] PROCESSSLIST`](/sql-statements/sql-statement-show-processlist.md)
       + [`SHOW SCHEMAS`](/sql-statements/sql-statement-show-schemas.md)
       + [`SHOW STATUS`](/sql-statements/sql-statement-show-status.md)
+      + [`SHOW TABLE NEXT_ROW_ID`](/sql-statements/sql-statement-show-table-next-rowid.md)
       + [`SHOW TABLE REGIONS`](/sql-statements/sql-statement-show-table-regions.md)
       + [`SHOW TABLE STATUS`](/sql-statements/sql-statement-show-table-status.md)
       + [`SHOW [FULL] TABLES`](/sql-statements/sql-statement-show-tables.md)

sql-statements/sql-statement-show-processlist.md

@@ -11,9 +11,9 @@ This statement lists the current sessions connected to the same TiDB server. The
 
 ## Synopsis
 
-**ShowStmt:**
+**ShowProcesslistStmt:**
 
-![ShowStmt](/media/sqlgram/ShowStmt.png)
+![ShowProcesslistStmt](/media/sqlgram/ShowProcesslistStmt.png)
 
 **OptFull:**
 

sql-statements/sql-statement-show-table-next-rowid.md

@@ -0,0 +1,63 @@
+---
+title: SHOW TABLE NEXT_ROW_ID
+summary: Learn the usage of `SHOW TABLE NEXT_ROW_ID` in TiDB.
+category: reference
+---
+
+# SHOW TABLE NEXT_ROW_ID
+
+`SHOW TABLE NEXT_ROW_ID` can be used to show the implicitly allocated global Row ID of a table.
+
+- For most of the tables, TiDB allocates a unique number for each record. The max allocated ID is persisted in the storage layer. Each TiDB server applies for a range of IDs on demand and caches them for ID allocation. This syntax can be used to query the next value to allocate, recorded in the storage layer. 
+- For the tables with integer primary key for optimization, TiDB maps the values in the primary key column to Row ID. Thus, `SHOW TABLE NEXT_ROW_ID` is meaningless for these tables. 
+
+## Synopsis
+
+**ShowTableNextRowIDStmt:**
+
+![ShowTableNextRowIDStmt](/media/sqlgram/ShowTableNextRowIDStmt.png)
+
+**TableName:**
+
+![TableName](/media/sqlgram/TableName.png)
+
+## Examples
+
+{{< copyable "sql" >}}
+
+```sql
+create table t(a int);
+Query OK, 0 rows affected (0.06 sec)
+```
+
+```sql
+# For newly created tables, NEXT_GLOBAL_ROW_ID is 1 because no Row ID is allocated.
+show table t next_row_id;
++---------+------------+-------------+--------------------+
+| DB_NAME | TABLE_NAME | COLUMN_NAME | NEXT_GLOBAL_ROW_ID |
++---------+------------+-------------+--------------------+
+| test    | t          | _tidb_rowid |                  1 |
++---------+------------+-------------+--------------------+
+1 row in set (0.00 sec)
+```
+
+```sql
+insert into t values (), (), ();
+Query OK, 3 rows affected (0.02 sec)
+Records: 3  Duplicates: 0  Warnings: 0
+```
+
+```sql
+show table t next_row_id;
+# Data have been written to the table. The TiDB server that inserts the data allocates and caches 30000 IDs at once. Thus, NEXT_GLOBAL_ROW_ID is 30001 now.
++---------+------------+-------------+--------------------+
+| DB_NAME | TABLE_NAME | COLUMN_NAME | NEXT_GLOBAL_ROW_ID |
++---------+------------+-------------+--------------------+
+| test    | t          | _tidb_rowid |              30001 |
++---------+------------+-------------+--------------------+
+1 row in set (0.00 sec)
+```
+
+## MySQL compatibility
+
+`SHOW TABLE NEXT_ROW_ID` is specific to TiDB.

sql-statements/sql-statement-show-table-status.md

@@ -11,17 +11,17 @@ This statement shows various statistics about tables in TiDB. If the statistics
 
 ## Synopsis
 
-**ShowStmt:**
+**ShowTableStatusStmt:**
 
-![ShowStmt](/media/sqlgram/ShowStmt.png)
+![ShowTableStatusStmt](/media/sqlgram/ShowTableStatusStmt.png)
 
-**ShowTargetFilterable:**
+**FromOrIn:**
 
-![ShowTargetFilterable](/media/sqlgram/ShowTargetFilterable.png)
+![FromOrIn](/media/sqlgram/FromOrIn.png)
 
-**ShowDatabaseNameOpt:**
+**StatusTableName:**
 
-![ShowDatabaseNameOpt](/media/sqlgram/ShowDatabaseNameOpt.png)
+![StatusTableName](/media/sqlgram/StatusTableName.png)
 
 ## Examples
 

sql-statements/sql-statement-show-warnings.md

@@ -11,13 +11,9 @@ This statement shows a list of warnings that occurred for previously executed st
 
 ## Synopsis
 
-**ShowStmt:**
+**ShowWarningsStmt:**
 
-![ShowStmt](/media/sqlgram/ShowStmt.png)
-
-**ShowTargetFilterable:**
-
-![ShowTargetFilterable](/media/sqlgram/ShowTargetFilterable.png)
+![ShowWarningsStmt](/media/sqlgram/ShowWarningsStmt.png)
 
 ## Examples