大部分情况下，框架都可以满足98%的需求，那剩下2%怎么办？

mybatis-mp作者：Ai东 已经替你们考虑，并设计了3个模板类供大家使用

1：普通sql模板-> CmdTemplate

2：函数模板-> FunTemplate

3：条件模板-> ConditionTemplate

如何使用？

1.只需要1列的情况：

1.1 普通模板

QueryChain queryChain = QueryChain.of(sysUserMapper);
queryChain.selectWithFun(SysUser::getRole_id, c -> CmdTemplate.create("count({0})+{1}", c, "1"));
queryChain.from(SysUser.class);
queryChain.and(cs -> ConditionTemplate.create("{0}+{1}={2}", cs[0], cs[1], 2), SysUser::getId, SysUser::getId);
queryChain.setReturnType(String.class);
String str = queryChain.get();

1.2 函数模板操作后 还可以继续调用框架自带的方法

QueryChain queryChain = QueryChain.of(sysUserMapper);
queryChain.selectWithFun(SysUser::getRole_id, c -> FunTemplate.create("count({0})",c).plus(1).concat(1,"2",3).length());
queryChain.from(SysUser.class);
queryChain.and(cs -> ConditionTemplate.create("{0}+{1}={2}", cs[0], cs[1], 2), SysUser::getId, SysUser::getId);
queryChain.setReturnType(String.class);
String str = queryChain.get();

1.3 条件模板

QueryChain queryChain = QueryChain.of(sysUserMapper);
queryChain.selectWithFun(SysUser::getRole_id, c -> FunTemplate.create("count({0})",c).plus(1).concat(1,"2",3).length());
queryChain.from(SysUser.class);
queryChain.and(cs -> ConditionTemplate.create("{0}+{1}={2}", cs[0], cs[1], 2), SysUser::getId, SysUser::getId);
queryChain.setReturnType(String.class);
String str = queryChain.get();

1. 需要多个列的情况

QueryChain queryChain = QueryChain.of(sysUserMapper);
queryChain.selectWithFun(SysUser::getRole_id, c -> FunTemplate.create("count({0})",c).plus(1).concat(1,"2",3).length());
queryChain.from(SysUser.class);
queryChain.and(cs -> ConditionTemplate.create("{0}+{1}={2}", cs[0], cs[1], 2), SysUser::getId, SysUser::getId);
queryChain.setReturnType(String.class);
String str = queryChain.get();

主要是这行代码：queryChain.and(cs -> ConditionTemplate.create("{0}+{1}={2}", cs[0], cs[1], 2), SysUser::getId, SysUser::getId);

咋样，赶紧加入mybatis-mp使用的行列吧！