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How do I detect if the ON UPDATE event fired with query in MySQL?
You can detect with the help of row_count(). If the row_count() returns 1 that means it is a new record. If it returns 2, that means the ON UPDATE event is fired with query. Following is the syntax −
select row_count();
Let us first create a table −
mysql> create table DemoTable1512 -> ( -> Value int , -> UNIQUE(Value) -> ); Query OK, 0 rows affected (0.60 sec)
Insert some records in the table using insert command −
mysql> insert into DemoTable1512 values(90) on duplicate key update Value=Value+10; Query OK, 1 row affected (0.09 sec)
Now you can check the on update event is fired with the help of above query −
mysql> select row_count();
This will produce the following output −
+-------------+ | row_count() | +-------------+ | 1 | +-------------+ 1 row in set (0.00 sec)
It returns 1 that means no.
Now you can insert same records again in the table using insert command −
mysql> insert into DemoTable1512 values(90) on duplicate key update Value=Value+10; Query OK, 2 rows affected (0.12 sec)
Now you can check the on update event is fired with the help of above query −
mysql> select row_count();
This will produce the following output −
+-------------+ | row_count() | +-------------+ | 2 | +-------------+ 1 row in set (0.00 sec)
Updated on: 11-Dec-2019
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