How to use parentheses to nest queries in mybatisplus where QueryWrapper
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Where QueryWrapper nested query in parentheses
The previous code looks like this:
QueryWrapper wrapper = new QueryWrapper (); wrapper.eq ("phoneNumber", phone); if (StringUtils.isEmpty (scenetype)) {wrapper.isNull ("scenetype"). Or (). Eq ("scenetype", ");} wrapper.eq (" delFlag "," 0 ")
The corresponding SQL statement is as follows:
WHERE (phoneNumber = 156 million dollars) AND scenetype IS NULL OR scenetype = "" AND delFlag = 0)
This is not the sql statement I want, and the data for the query is incorrect. The query for scenetype should be enclosed and meet one of its conditions, that is:
WHERE (phoneNumber = 156 million dollars) 8888 AND (scenetype IS NULL OR scenetype = ") AND delFlag = 0)
The corresponding code should be written like this:
QueryWrapper wrapper = new QueryWrapper (); wrapper.eq ("phoneNumber", phone); if (StringUtils.isEmpty (scenetype)) {wrapper.and (e-> e.isNull ("scenetype") .or (). Eq ("scenetype", "));} wrapper.eq (" delFlag "," 0 "); mybatisplus query statement with parentheses (.or (), .and ())
Java Code:
QueryWrapper wrapper = new QueryWrapper (); wrapper.ne ("id", param.getId ()) wrapper.and (QueryWrapper-> QueryWrapper.eq ("name", name). Or (). Eq ("mark", mark); entityMapper.selectList (wrapper)
Equivalent sql
SELECT id FROM t_entity WHERE (id? AND (name =? OR mark =?))
Each and is equivalent to a parenthesis
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