mybatis if函数

MyBatis provides an if statement to conditionally include or exclude parts of a SQL query based on specific conditions. The if statement is used within the XML configuration file or annotated interface to dynamically generate SQL statements.

Here's an example of using the if statement in MyBatis:

<select id="getUserById" resultType="User">
  SELECT * FROM users
  WHERE id = #{id}
  <if test="name != null">
    AND name = #{name}
  </if>
</select>

In this example, the if statement checks if the `name` parameter is not null. If it is not null, it appends an additional condition to the SQL query. Otherwise, the additional condition is excluded.

You can use various logical operators, comparisons, and functions within the test attribute of the if statement to construct more complex conditions.

Note that the syntax may vary slightly depending on the version of MyBatis you are using. Make sure to refer to the official documentation for the version you are working with.