用MySQL替换逗号分隔结果上的数字？
为此，将CASE语句与FIND_IN_SET()一起使用。让我们首先创建一个表-
mysql> create table DemoTable1629
-> (
-> Month varchar(100)
-> );使用insert命令在表中插入一些记录。
mysql> insert into DemoTable1629 values('2,4,6');
mysql> insert into DemoTable1629 values('1,3,5,12');
mysql> insert into DemoTable1629 values('7,8,9,10');使用select语句显示表中的所有记录-
mysql> select * from DemoTable1629;
这将产生以下输出-
+----------+ | Month | +----------+ | 2,4,6 | | 1,3,5,12 | | 7,8,9,10 | +----------+ 3 rows in set (0.00 sec)
以下是替换逗号分隔结果上的数字的查询-
mysql> select trim(trailing ',' from concat(
-> CASE WHEN FIND_IN_SET(1, Month) THEN 'January,' ELSE '' END,
-> CASE WHEN FIND_IN_SET(2, Month) THEN 'Feburary,' ELSE '' END,
-> CASE WHEN FIND_IN_SET(3, Month) THEN 'March,' ELSE '' END,
-> CASE WHEN FIND_IN_SET(4, Month) THEN 'April,' ELSE '' END,
-> CASE WHEN FIND_IN_SET(5, Month) THEN 'May,' ELSE '' END,
-> CASE WHEN FIND_IN_SET(6, Month) THEN 'June,' ELSE '' END,
-> CASE WHEN FIND_IN_SET(7, Month) THEN 'July,' ELSE '' END,
-> CASE WHEN FIND_IN_SET(8, Month) THEN 'August,' ELSE '' END,
-> CASE WHEN FIND_IN_SET(9, Month) THEN 'September,' ELSE '' END,
-> CASE WHEN FIND_IN_SET(10,Month) THEN 'October,' ELSE '' END,
-> CASE WHEN FIND_IN_SET(11,Month) THEN 'November,' ELSE '' END,
-> CASE WHEN FIND_IN_SET(12,Month) THEN 'December,' ELSE '' END
-> ))
-> from DemoTable1629;这将产生以下输出-
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| trim(trailing ',' from concat(
CASE WHEN FIND_IN_SET(1, Month) THEN 'January,' ELSE '' END,
CASE WHEN FIND_IN_SET(2, Month) THEN 'Feburary,' ELSE '' END,
CASE WHEN FIND_IN_SET(3, Month) THEN 'Marh,' ELSE '' END,
CASE WHEN FIND_IN_SET(4, Mon |
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Feburary,April,June |
| January,March,May,December |
| July,August,September,October |
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
3 rows in set (0.04 sec)