java
Page<Record> queryAll(String memberId, String memberName);
xml
<select id="queryAll" resultMap="recordResultMap">
SELECT *
FROM record
WHERE member_id LIKE CONCAT('%', #{memberId}, '%')
AND member_name LIKE CONCAT('%', #{memberName}, '%')
ORDER BY ID DESC
</select>-
在 Spring Boot 项目中，使用 MyBatis PostgreSQL，执行上述代码，传入的参数为 null 时，出现如下错误信息
org.springframework.jdbc.BadSqlGrammarException:
Error querying database. Cause: org.postgresql.util.PSQLException: 错误: 无法确定参数 $1 的数据类型
The error may exist in file ...
The error may involve defaultParameterMap
The error occurred while setting parameters
SQL: SELECT count(0) FROM record WHERE member_id LIKE CONCAT('%', ?, '%') AND member_name LIKE CONCAT('%', ?, '%')
Cause: org.postgresql.util.PSQLException: 错误: 无法确定参数 $1 的数据类型
; bad SQL grammar []
at org.springframework.jdbc.support.SQLStateSQLExceptionTranslator.doTranslate(SQLStateSQLExceptionTranslator.java:99)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:70)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:79)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:79)
at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:92)...Caused by: org.postgresql.util.PSQLException: 错误: 无法确定参数 $1 的数据类型
at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2676)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:2366)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:356)
at org.postgresql.jdbc.PgStatement.executeInternal(PgStatement.java:496)
at org.postgresql.jdbc.PgStatement.execute(PgStatement.java:413)...
问题原因
- 在 PostgreSQL 中，传入的参数为 null，CONCAT 函数无法推断参数的数据类型
处理策略
- 使用条件判断动态 SQL
xml
<select id="queryAll" resultMap="recordResultMap">
SELECT *
FROM record
WHERE 1=1
<if test="memberId != null and memberId != ''">
AND member_id LIKE CONCAT('%', #{memberId}, '%')
</if>
<if test="memberName != null and memberName != ''">
AND member_name LIKE CONCAT('%', #{memberName}, '%')
</if>
ORDER BY ID DESC
</select>