Fix MyBatis selectKey Error – Guide

The selectKey in Mybatis is used to retrieve the automatically generated primary key value after an insert operation. If an error occurs while using selectKey, it may be due to several possible reasons.

1. There is an error in the SQL statement: Please ensure that the selectKey statement’s SQL syntax is correct, including the field names and table names.
2. Parameter type mismatch: please check if the parameter types in selectKey match the database field types, for example, the returned primary key value should be set as an Integer type, while the database primary key is of type int.
3. Lack of primary key generation strategy: You need to specify the primary key generation strategy in selectKey, for example in MySQL you can use the order attribute of selectKey to specify the primary key generation strategy.

If all of the above issues have been ruled out, but selectKey still throws an error, it may be necessary to examine specific error information, such as exception stack traces or log files, in order to more accurately locate the problem. Additionally, you can also try referring to Mybatis official documentation or seek help from Mybatis-related community or forum.