云数据库OceanBase入门教程 OceanBase INSERT

2024-02-26 开发教程 云数据库OceanBase入门教程 匿名 3

描述

该语句用于添加一个或多个记录到表中。

格式

INSERT [hint_options] { single_table_insert | multi_table_insert }
single_table_insert:
{ INTO insert_table_clause opt_nologging '(' column_list ')' values_clause [{ RETURNING | RETURN } returning_exprs [into_clause]]
| INTO insert_table_clause opt_nologging '(' ')' values_clause [{ RETURNING | RETURN } returning_exprs [into_clause]]
| INTO insert_table_clause opt_nologging values_clause [{ RETURNING | RETURN } returning_exprs [into_clause]]
}
opt_nologging: { NOLOGGING | /*EMPTY*/ }
returning_exprs:
projection [, ...]
insert_into_clause:
{ INTO into_var_list | BULK COLLECT INTO into_var_list}
into_var_list:
{ USER_VARIABLE | ref_name } [, ...]
values_clause:
VALUES ({ expr | DEFAULT } [, { expr | DEFAULT } ]... )
multi_table_insert:
{ ALL { insert_into_clause [ values_clause ] [error_logging_clause] }
| conditional_insert_clause
} subquery
conditional_insert_clause:
[ ALL | FIRST ]
WHEN condition
THEN insert_into_clause
[ values_clause ]
[ error_logging_clause ]
[ insert_into_clause [ values_clause ] [ error_logging_clause ] ]...
[ WHEN condition
THEN insert_into_clause
[ values_clause ]
[ error_logging_clause ]
[ insert_into_clause [ values_clause ] [ error_logging_clause ] ]...
]...
[ ELSE insert_into_clause
[ values_clause ]
[ error_logging_clause ]
[ insert_into_clause [ values_clause ] [ error_logging_clause ] ]...
]
error_logging_clause:
LOG ERRORS [ INTO [schema.] table ] [ (simple_expression) ] [ REJECT LIMIT { integer | UNLIMITED } ]

参数解释

参数

描述

hint_options

指定 Hint 选项。

single_table_insert

单表插入。

insert_table_clause

指定的插入的表,可以是基表、可更新视图、特殊子查询。

opt_nologging

尽量减少插入时的日志信息。

column_list

指定要插入的列名。

returning_exprs

返回插入数据之后的投影列。

insert_into_clause

将插入数据之后的列值插入到指定列表中。

multi_table_insert

多表插入。

conditional_insert_clause

带条件的多表插入。

  • ALL:遍历所有匹配条件的分支,只要满足条件就会将数据插入对应的表。

  • FIRST:找到第一个满足条件的分支后,将数据插入该分支对应的表,不会再继续检查剩余分支的条件是否满足。

注意
特殊子查询指的类似于可更新视图对应的子查询,这类子查询不应该包含复杂的算子(比如 group by/distinct/window function 等)

示例

示例表及数据基于以下定义:

obclient>CREATE TABLE t1(c1 INT PRIMARY KEY, c2 INT,c3 INT);
Query OK, 0 rows affected (0.10 sec)
obclient> SELECT * FROM t;
Empty set (0.02 sec)
  • 单表插入:向表 t 中插入一行数据。

obclient> INSERT INTO t VALUES(1,2,3);
Query OK, 1 row affected (0.00 sec)
obclient> SELECT * FROM t;
+----+------+------+
| C1 | C2 | C3 |
+----+------+------+
| 1 | 2 | 3 |
+----+------+------+
1 row in set (0.00 sec)
  • 单表插入:直接向子查询中插入数据

obclient>INSERT INTO (SELECT * FROM t) VALUES(1,2,3);
Query OK, 1 row affected (0.00 sec)
obclient> SELECT * FROM t;
+----+------+------+
| C1 | C2 | C3 |
+----+------+------+
| 1 | 2 | 3 |
+----+------+------+
1 row in set (0.01 sec)
  • 单表插入:包含 RETURNING子句。

obclient>INSERT INTO t VALUES(1,2,3) RETURNING c1;
+----+
| C1 |
+----+
| 1 |
+----+
1 row in set (0.00 sec)
obclient>SELECT * FROM t;
+----+------+------+
| C1 | C2 | C3 |
+----+------+------+
| 1 | 2 | 3 |
+----+------+------+
1 row in set (0.00 sec)
  • 普通的多表插入:当表 t 中有至少一行数据时,向表 t1 插入一行数据 (1,1,1),向表 t2 插入一行数据 (2,2,2)。

obclient>INSERT ALL INTO t1 VALUES(1,1,1) INTO t2 VALUES(2,2,2) SELECT * FROM t
WHERE ROWNUM< 2;
Query OK, 2 rows affected (0.01 sec)
Records: 2 Duplicates: 0 Warnings: 0
obclient>SELECT * FROM t1;
+----+------+------+
| C1 | C2 | C3 |
+----+------+------+
| 1 | 1 | 1 |
+----+------+------+
1 row in set (0.02 sec)
obclient>SELECT * FROM t2;
+----+------+------+
| C1 | C2 | C3 |
+----+------+------+
| 2 | 2 | 2 |
+----+------+------+
1 row in set (0.01 sec)
  • 带条件的多表插入:使用 INSERT ALL,当表 t 中 c2 的值大于 1 时,向表 t1 中插入数据 (1,1,1);当表 t 中 c3 的值大于 1 时,向表 t2 中插入数据 (2,2,2);如果都不满足,则向表 t1 中插入数据 (3,3,3)。

obclient>DELETE FROM (SELECT * FROM t);
Query OK, 4 rows affected (0.04 sec)
obclient>INSERT INTO t VALUES(1,2,3);
Query OK, 1 row affected (0.00 sec)
obclient>INSERT ALL
WHEN c2 > 1 THEN INTO t1 VALUES(1,1,1)
WHEN c3 > 1 THEN INTO t2 VALUES(2,2,2)
ELSE INTO t1 VALUES(3,3,3) SELECT c2,c3 FROM t;
Query OK, 2 rows affected (0.01 sec)
Records: 2 Duplicates: 0 Warnings: 0
obclient>SELECT * FROM t1;
+----+------+------+
| C1 | C2 | C3 |
+----+------+------+
| 1 | 1 | 1 |
+----+------+------+
1 row in set (0.00 sec)
obclient>SELECT * FROM t2;
+----+------+------+
| C1 | C2 | C3 |
+----+------+------+
| 2 | 2 | 2 |
+----+------+------+
1 row in set (0.00 sec)
  • 带条件的多表插入:使用 INSERT FIRST,当表 t 中 c2 的值大于 1 时,向表 t1 中插入数据 (1,1,1),向表 t2 中插入数据 (4,4,4);当表 t 中 c3 的值大于 1 时,向表 t2 中插入数据 (2,2,2);如果都不满足,则向表 t1 中插入数据 (3,3,3)。

obclient>DELETE FROM (SELECT * FROM t);
Query OK, 4 rows affected (0.04 sec)
obclient>INSERT INTO t VALUES(1,2,3);
Query OK, 1 row affected (0.00 sec)
obclient>INSERT ALL
WHEN c2 > 1 THEN INTO t1 VALUES(1,1,1) INTO t2 VALUES(4,4,4)
when c3 > 1 THEN INTO t2 VALUES(2,2,2)
ELSE INTO t1 VALUES(3,3,3) SELECT c2,c3 FROM t;
Query OK, 2 rows affected (0.01 sec)
Records: 2 Duplicates: 0 Warnings: 0
obclient>SELECT * FROM t1;
+----+------+------+
| C1 | C2 | C3 |
+----+------+------+
| 1 | 1 | 1 |
+----+------+------+
1 row in set (0.00 sec)
obclient>SELECT * FROM t2;
+------+------+------+
| C1 | C2 | C3 |
+------+------+------+
| 4 | 4 | 4 |
| 2 | 2 | 2 |
+------+------+------+
2 rows in set (0.00 sec)