如果 table 为空，则插入多条记录

Question

我有一个场景，如果 table 为空，我必须插入多条记录。我的 sql 脚本运行每次我运行我的服务器。我不使用 H2 数据库，所以我可以插入重复键。我用的是 myBatis。我希望查询仅在 table 为空时插入。

我的插入查询如下：

LOCK TABLES `t002_seat_mst` WRITE;
INSERT INTO `t002_seat_mst` VALUES (2020,1,1,0,0,1,0,'228A'),(2021,1,2,0,0,1,0,'229A'),
    (2022,1,3,0,0,1,0,'231A'),(2023,1,4,0,0,1,0,'233A'),(2024,1,5,0,0,1,0,'235A'),
    (2025,1,6,0,0,1,0,'237A'),(2026,1,7,0,0,1,0,'239A'),(2027,1,8,0,0,1,0,'240A'),
    (2028,1,9,0,0,1,0,'242A'),(2029,1,10,0,0,1,0,'244A'),(2030,1,11,0,0,1,0,'246A');
UNLOCK TABLES;

我怎样才能做到这一点？

Answer 1

测试

LOCK TABLES `t002_seat_mst` AS t1 WRITE, `t002_seat_mst` AS t2 READ;

INSERT INTO t002_seat_mst AS t1
SELECT * 
FROM ( SELECT 2020 a,1 b,1 c,0 d,0 e,1 f,0 g,'228A' h UNION ALL
       SELECT 2021,1,2,0,0,1,0,'229A' UNION ALL
       SELECT 2022,1,3,0,0,1,0,'231A' UNION ALL
       SELECT 2023,1,4,0,0,1,0,'233A' UNION ALL
       SELECT 2024,1,5,0,0,1,0,'235A' UNION ALL
       SELECT 2025,1,6,0,0,1,0,'237A' UNION ALL
       SELECT 2026,1,7,0,0,1,0,'239A' UNION ALL
       SELECT 2027,1,8,0,0,1,0,'240A' UNION ALL
       SELECT 2028,1,9,0,0,1,0,'242A' UNION ALL
       SELECT 2029,1,10,0,0,1,0,'244A' UNION ALL
       SELECT 2030,1,11,0,0,1,0,'246A' ) data
WHERE NOT EXISTS ( SELECT NULL
                   FROM t002_seat_mst AS t2 );

UNLOCK TABLES;

如果 table 为空，则插入多条记录

Insert multiple records if table is empty

mysql

sql

h2

mybatis

spring-boot