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fixed: 无法优化 COUNT 查询的问题，关闭：https://gitee.com/mybatis-flex/mybatis-flex/issues/IAYAHL。

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This commit is contained in:
王帅 2024-10-28 16:27:41 +08:00
parent 98b3c7b92e
commit 37e76da4d9
1 changed files with 13 additions and 10 deletions
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23
mybatis-flex-core/src/main/java/com/mybatisflex/core/util/MapperUtil.java
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@ -69,17 +69,20 @@ public class MapperUtil {
.select(count().as("total"))
.from(queryWrapper).as("t");
}
public static QueryWrapper rawCountQueryWrapper(QueryWrapper queryWrapper,List<QueryColumn> customCountColumns) {
return customCountColumns!=null?QueryWrapper.create()
public static QueryWrapper rawCountQueryWrapper(QueryWrapper queryWrapper, List<QueryColumn> customCountColumns) {
return customCountColumns != null ? QueryWrapper.create()
.select(customCountColumns)
.from(queryWrapper).as("t"):rawCountQueryWrapper(queryWrapper);
.from(queryWrapper).as("t") : rawCountQueryWrapper(queryWrapper);
}
/**
* 优化 COUNT 查询语句。
*/
public static QueryWrapper optimizeCountQueryWrapper(QueryWrapper queryWrapper) {
return optimizeCountQueryWrapper(queryWrapper, Collections.singletonList(count().as("total")));
}
/**
* 优化 COUNT 查询语句。
*/
@ -88,10 +91,10 @@ public class MapperUtil {
QueryWrapper clone = queryWrapper.clone();
List<UnionWrapper> unions = CPI.getUnions(clone);
if(!CollectionUtil.isEmpty(unions)){
if (!CollectionUtil.isEmpty(unions)) {
List<UnionWrapper> newUnions = new ArrayList<>(unions.size());
for (UnionWrapper union : unions) {
QueryWrapper unionQuery = optimizeCountQueryWrapper(union.getQueryWrapper().clone(),null);
QueryWrapper unionQuery = optimizeCountQueryWrapper(union.getQueryWrapper().clone(), null);
UnionWrapper clone1 = union.clone();
clone1.setQueryWrapper(unionQuery);
newUnions.add(clone1);
@ -108,17 +111,17 @@ public class MapperUtil {
// 如果有 distinct、group by、having 等语句则不优化
// 这种一旦优化了就会造成 count 语句查询出来的值不对
if (hasDistinct(selectColumns) || hasGroupBy(groupByColumns) || havingCondition != null) {
return clone;
return rawCountQueryWrapper(clone);
}
// 判断能不能清除 join 语句
if (canClearJoins(clone)) {
CPI.setJoins(clone, null);
}
// 将 select 里面的列换成 COUNT(*) AS `total`
if(customCountColumns!=null){
if(hasUnion(clone)){
return rawCountQueryWrapper(clone,customCountColumns);
}else {
if (customCountColumns != null) {
if (hasUnion(clone)) {
return rawCountQueryWrapper(clone, customCountColumns);
} else {
CPI.setSelectColumns(clone, customCountColumns);
}
}