Oracle23ai新特性单个INSERT INTO语句后跟多个VALUES子句

1、新特性简介

本次测试数据库版本Oracle 23ai Free Release 23.0.0.0.0

SYS@FREE> select * from v$version;

BANNER
--------------------------------------------------------------------------------
BANNER_FULL
--------------------------------------------------------------------------------
BANNER_LEGACY
--------------------------------------------------------------------------------
    CON_ID
----------
Oracle Database 23ai Free Release 23.0.0.0.0 - Develop, Learn, and Run for Free
Oracle Database 23ai Free Release 23.0.0.0.0 - Develop, Learn, and Run for Free
Version 23.4.0.24.05
Oracle Database 23ai Free Release 23.0.0.0.0 - Develop, Learn, and Run for Free
         0

BANNER
--------------------------------------------------------------------------------
BANNER_FULL
--------------------------------------------------------------------------------
BANNER_LEGACY
--------------------------------------------------------------------------------
    CON_ID
----------

Oracle23ai新特性，直接插入多行数据并不总是使用 INSERT ALL 语法。Oracle 提供了一种更简洁的方法来一次性插入多行数据，即使用单个 INSERT INTO 语句后跟多个 VALUES 子句。还可以使用values语句构建临时表。values语句构建数据和merge语句组合使用 。

2、 插入多行数据

在INSERT语句中，也可以实现多行的直接插入。

SYS@FREE> conn testuser/oracle@FREEPDB1
Connected.

TESTUSER@FREEPDB1> create table t_multirows (id number,infoname varchar2(32));
Table created.

TESTUSER@FREEPDB1> insert into t_multirows values(1,'oracle23c'),(2,'oracle23ai'),(3,'mysql8.4');

3 rows created.

TESTUSER@FREEPDB1> commit;
Commit complete.

TESTUSER@FREEPDB1> col infoname format a30
TESTUSER@FREEPDB1> select * from t_multirows;

        ID INFONAME
---------- ------------------------------
         1 oracle23c
         2 oracle23ai
         3 mysql8.4

3、使用values语句构建临时表

TESTUSER@FREEPDB1> select * from (values(1,'multiple'),(2,'values')) T (id,nameinfo);

        ID NAMEINFO
---------- ------------------------
         1 multiple
         2 values

4、values语句构建数据和cte 组合使用

cte (common table expressions)公用表表达式。

TESTUSER@FREEPDB1> with cte_values (id,nameinfo) as (values(1,'common'),(2,'table'),(3,'expressions')) select * from cte_values;

        ID NAMEINFO
---------- --------------------
         1 common
         2 table
         3 expressions
         
-- Oracle19c新增的自增id特性 generated by default as identity
CREATE TABLE t_identity
(
id NUMBER generated by DEFAULT AS identity ,
nameinfo varchar2(32),
sysguid varchar2(36),
CONSTRAINT pk_t_identity_id PRIMARY KEY(id)
);
-- sqlplus testuser/oracle@FREEPDB1
INSERT INTO t_identity(nameinfo,sysguid) values('generated by',sys_guid()),('DEFAULT',sys_guid()),('AS identity',sys_guid());
COMMIT;
-- 查询数据表
TESTUSER@FREEPDB1> SELECT * FROM  t_identity;

        ID NAMEINFO                       SYSGUID
---------- ------------------------------ ------------------------------------
         1 generated by                   18EFA5E23DDC0BA1E063E650A8C05A76
         2 DEFAULT                        18EFA5E23DDD0BA1E063E650A8C05A76
         3 AS identity                    18EFA5E23DDE0BA1E063E650A8C05A76
-- 再次插入两行数据
INSERT INTO t_identity(nameinfo,sysguid) values('get sys_guid',sys_guid()),('䶮中国字',sys_guid());
COMMIT;

TESTUSER@FREEPDB1> SELECT * FROM  t_identity;

        ID NAMEINFO                       SYSGUID
---------- ------------------------------ ------------------------------------
         1 generated by                   18EFA5E23DDC0BA1E063E650A8C05A76
         2 DEFAULT                        18EFA5E23DDD0BA1E063E650A8C05A76
         3 AS identity                    18EFA5E23DDE0BA1E063E650A8C05A76
         4 get sys_guid                   18EFA5E23DDF0BA1E063E650A8C05A76
         5 䶮中国字                       18EFA5E23DE00BA1E063E650A8C05A76

5、values语句构建数据和merge语句组合使用

MERGE into t_identity t1 
using  (values(4,'values meger',sys_guid()),(7,'table',sys_guid()),(8,'expressions',sys_guid())) t2 (ID,nameinfo,sysguid) 
on (t2.id=t1.id)
when matched then UPDATE set t1.nameinfo=t2.nameinfo,t1.sysguid=t2.sysguid
when not matched then insert (t1.id,t1.nameinfo,t1.sysguid) values(t2.id,t2.nameinfo,t2.sysguid);

TESTUSER@FREEPDB1> SELECT * FROM  t_identity;

        ID NAMEINFO                       SYSGUID
---------- ------------------------------ ------------------------------------
         1 generated by                   18EFA5E23DDC0BA1E063E650A8C05A76
         2 DEFAULT                        18EFA5E23DDD0BA1E063E650A8C05A76
         3 AS identity                    18EFA5E23DDE0BA1E063E650A8C05A76
         4 values meger                   18EFA5E23DE10BA1E063E650A8C05A76
         5 䶮中国字                       18EFA5E23DE00BA1E063E650A8C05A76
         7 table                          18EFA5E23DE20BA1E063E650A8C05A76
         8 expressions                    18EFA5E23DE30BA1E063E650A8C05A76

7 rows selected.
-- 可以看到ID=4的NAMEINFO='values meger'，MERGE into字句执行之前是'get sys_guid'
-- 即ID关联匹配到的数据执行了更新操作,ID没有关联匹配到的数据执行了插入操作