mybatis-plus 使用Condition拼接Sql语句各方法的用法

mybatis-plus Condition拼接Sql语句各方法

1.setSqlSelect—用于添加查询的列信息

public Wrapper<T> setSqlSelect(String... columns) {
       StringBuilder builder = new StringBuilder();
       String[] arr = columns;
       int len = columns.length;
       for(int i = 0; i$ < len; ++i$) {
           String column = arr$[i$];
           if (StringUtils.isNotEmpty(column)) {
               if (builder.length() > 0) {
                   builder.append(",");
               }
               builder.append(column);
           }
       }
       this.sqlSelect = builder.toString();
       return this;
   }

2.eq—拼接等于的where语句 column=params

public Wrapper<T> eq(boolean condition, String column, Object params) {
       if (condition) {
           this.sql.WHERE(this.formatSql(String.format("％s = {0}", column), params));
       }
       return this;
   }

3.ne—拼接不等于的where语句 column<>params

public Wrapper<T> ne(boolean condition, String column, Object params) {
       if (condition) {
           this.sql.WHERE(this.formatSql(String.format("％s <> {0}", column), params));
       }
       return this;
   }

4.allEq–拼接数据以map封装的等于的where语句

public Wrapper<T> allEq(boolean condition, Map<String, Object> params) {
       if (condition && MapUtils.isNotEmpty(params)) {
           Iterator iterator = params.entrySet().iterator();
           while(iterator.hasNext()) {
               Entry<String, Object> entry = (Entry)iterator.next();
               Object value = entry.getValue();
               if (StringUtils.checkValNotNull(value)) {
                   this.sql.WHERE(this.formatSql(String.format("％s = {0}", entry.getKey()), entry.getValue()));
               }
           }
       }
       return this;
   }

5.gt—-拼接大于号的where语句

public Wrapper<T> gt(boolean condition, String column, Object params) {
       if (condition) {
           this.sql.WHERE(this.formatSql(String.format("％s > {0}", column), params));
       }
       return this;
   }

6.ge–拼接大于等于号的where语句 （代码类似5）

7.lt—拼接小于号的where语句

8.le—小于等于

/**
        *
        AND (user_name=#{ew.paramNameValuePairs.MPGENVAL1} AND id=1)
        OR (user_status=#{ew.paramNameValuePairs.MPGENVAL2} OR status=1
        AND user_nickname NOT LIKE #{ew.paramNameValuePairs.MPGENVAL3})
        AND (new=xx AND hhh LIKE #{ew.paramNameValuePairs.MPGENVAL4})
        AND (pwd=11 AND n1 IS NOT NULL AND n2 IS NOT NULL AND n3 IS NULL)
        GROUP BY x1, x2,x3
        HAVING (x1=11 AND x3=433)
        ORDER BY dd, d1,d2
        */
       ew.where("user_name={0}", "'zhangsan'").and("id=1")
               .orNew("user_status={0}", "0").or("status=1")
               .notLike("user_nickname", "notvalue")
               .andNew("new=xx").like("hhh", "ddd")
               .andNew("pwd=11").isNotNull("n1,n2").isNull("n3")
               .groupBy("x1").groupBy("x2,x3")
               .having("x1=11").having("x3=433")
               .orderBy("dd").orderBy("d1,d2");

9.and — 在没有出现下一个andNew或者orNew之前的所有where条件在一个括号里

10.andNew –新建一组and语句

11.or,orNew–同上

mybatis-plus 自定义sql语句

@Override
   public Map<String, Object> kccxhj(Term term) throws Exception{
       QueryWrapper<EZShangPin> wrapper=new QueryWrapper<>();
       if(MyStrUtils.isNotEmpty(term.getQ())){
           CWMSTmdrdmx tmdrdmx=new CWMSTmdrdmx();
           tmdrdmx.setTm(term.getQ());
           tmdrdmx.setSl(1);
           tmService.recongnizeSptm(tmdrdmx);
           //log("tmdrdmx",tmdrdmx);
           if(tmdrdmx.getResult()==0){
               wrapper.eq("spdm",tmdrdmx.getSpdm());
           }else{
               wrapper.like("spdm+'_'+spmc+'_'+isnull(zjf,'')", term.getQ());
           }
       }
       wrapper.eq(MyStrUtils.isNotEmpty(term.getPpdm()),"fjsx1",term.getPpdm());
       wrapper.eq(MyStrUtils.isNotEmpty(term.getDldm()),"fjsx2",term.getDldm());
       wrapper.eq(MyStrUtils.isNotEmpty(term.getJjdm()),"fjsx3",term.getJjdm());
       wrapper.eq(MyStrUtils.isNotEmpty(term.getNddm()),"fjsx4",term.getNddm());
       wrapper.eq("isnull(tzsy,0)", 0);
       wrapper.eq("ckdm", term.getCurrentsddm());
       return repMapper.kccxhj(wrapper);
   }

@Mapper
@Repository
public interface RepMapper extends BaseMapper {
   Map<String, Object> kccxhj(@Param(Constants.WRAPPER) QueryWrapper wrapper);
}

  <select id="kccxhj" resultType="java.util.Map">
       SELECT SUM(SL) AS zsl,sum(sl*bzsj) as zje
       from(
               select ckdm,ShangPin.spdm,ShangPin.spmc,ShangPin.zjf,shanpin.bzsj,ShangPin.FJSX1,ShangPin.FJSX2,ShangPin.FJSX3,ShangPin.FJSX4,SPKCB.SL
               from shangpin,SPKCB
               where shangpin.spdm=spkcb.SPDM
       ) a
       ${ew.customSqlSegment}
   </select>

来源：https://blog.csdn.net/qq_36752632/article/details/79035980