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How to write a valid MySQL query and update with a custom variable?
Let us first create a table −
mysql> create table DemoTable2027 -> ( -> UserId int -> ); Query OK, 0 rows affected (0.65 sec)
Insert some records in the table using insert command −
mysql> insert into DemoTable2027 values(10); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable2027 values(20); Query OK, 1 row affected (0.28 sec) mysql> insert into DemoTable2027 values(31); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable2027 values(11); Query OK, 1 row affected (0.12 sec)
Display all records from the table using select statement −
mysql> select *from DemoTable2027;
This will produce the following output −
+--------+ | UserId | +--------+ | 10 | | 20 | | 31 | | 11 | +--------+ 4 rows in set (0.00 sec)
Here is the query to write a valid query and update with a custom variable −
mysql> set @uId:=100; Query OK, 0 rows affected (0.00 sec) mysql> update DemoTable2027 -> set UserId=(@uId:=@uId+10); Query OK, 4 rows affected (0.13 sec) Rows matched: 4 Changed: 4 Warnings: 0
Let us check the table records. −
mysql> select *from DemoTable2027;
This will produce the following output −
+--------+ | UserId | +--------+ | 110 | | 120 | | 130 | | 140 | +--------+ 4 rows in set (0.00 sec)
Updated on: 06-Apr-2020
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