模糊查询:
工作中用到,写三种用法吧
1. sql中字符串拼接
SELECT * FROM tableName WHERE name LIKE CONCAT(CONCAT('%', #{text}), '%');
2. 使用 ${...} 代替 #{...} (不能防止sql注入 #{}---> 可以防止sql注入的问题)
SELECT * FROM tableName WHERE name LIKE '%${text}%';
3. 程序中拼接
Java
// or String searchText = "%" + text + "%";
String searchText = new StringBuilder("%").append(text).append("%").toString();
parameterMap.put("text", searchText);
SqlMap.xml
SELECT * FROM tableName WHERE name LIKE #{text};
异常:
java.lang.IllegalArgumentException: modify is ambiguous in Mapped Statements collection (try using the full name including the namespace, or rename one of the entries)
at org.apache.ibatis.session.Configuration$StrictMap.get(Configuration.java:466)
at org.apache.ibatis.session.Configuration.getMappedStatement(Configuration.java:349)
at org.apache.ibatis.binding.MapperMethod.setupCommandType(MapperMethod.java:137)
at org.apache.ibatis.binding.MapperMethod.<init>(MapperMethod.java:46)
at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:34)
at $Proxy10.modify(Unknown Source)
抛出这个异常的原因可能是因为mapper.xml配置文件中<mapper>的namespace属性配置错误造成的,没有根据命名空间的值(全称类名)找到相应映射接口。
如:<mapper namespace="com.xxx.xxx.mapper.TestMapper" >