本文整理汇总了Java中net.sf.jsqlparser.statement.select.Distinct类的典型用法代码示例。如果您正苦于以下问题:Java Distinct类的具体用法?Java Distinct怎么用?Java Distinct使用的例子?那么恭喜您, 这里精选的类代码示例或许可以为您提供帮助。
Distinct类属于net.sf.jsqlparser.statement.select包,在下文中一共展示了Distinct类的3个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于我们的系统推荐出更棒的Java代码示例。
示例1: sqlCountOptimize
import net.sf.jsqlparser.statement.select.Distinct; //导入依赖的package包/类
/**
* 获取select的count语句
*
* @param originalSql
* selectSQL
* @return
*/
public static String sqlCountOptimize(String originalSql) {
Assert.hasLength(originalSql);
String sqlCount;
try {
Select selectStatement = (Select) CCJSqlParserUtil.parse(originalSql);
PlainSelect plainSelect = (PlainSelect) selectStatement.getSelectBody();
Distinct distinct = plainSelect.getDistinct();
List<Expression> groupBy = plainSelect.getGroupByColumnReferences();
// 优化Order by
List<OrderByElement> orderBy = plainSelect.getOrderByElements();
// 添加包含groupby 不去除orderby
if (CollectionUtils.isEmpty(groupBy) && CollectionUtils.isNotEmpty(orderBy)) {
plainSelect.setOrderByElements(null);
}
if (distinct != null || CollectionUtils.isNotEmpty(groupBy)) {
return String.format(SQL_BASE_COUNT, selectStatement.toString());
}
List<SelectItem> selectCount = countSelectItem();
plainSelect.setSelectItems(selectCount);
sqlCount = selectStatement.toString();
} catch (Exception e) {
sqlCount = String.format(SQL_BASE_COUNT, originalSql);
}
return sqlCount;
}
开发者ID:baomidou,项目名称:hibernate-plus,代码行数:33,代码来源:SqlUtils.java
示例2: jsqlparserCount
import net.sf.jsqlparser.statement.select.Distinct; //导入依赖的package包/类
/**
* jsqlparser方式获取select的count语句
*
* @param originalSql selectSQL
* @return
*/
public static String jsqlparserCount(String originalSql) {
String sqlCount;
try {
Select selectStatement = (Select) CCJSqlParserUtil.parse(originalSql);
PlainSelect plainSelect = (PlainSelect) selectStatement.getSelectBody();
Distinct distinct = plainSelect.getDistinct();
List<Expression> groupBy = plainSelect.getGroupByColumnReferences();
// 优化Order by
List<OrderByElement> orderBy = plainSelect.getOrderByElements();
// 添加包含groupby 不去除orderby
if (CollectionUtils.isEmpty(groupBy) && CollectionUtils.isNotEmpty(orderBy)) {
plainSelect.setOrderByElements(null);
}
// 包含 distinct、groupBy不优化
if (distinct != null || CollectionUtils.isNotEmpty(groupBy)) {
sqlCount = String.format(SqlUtils.SQL_BASE_COUNT, selectStatement.toString());
return sqlCount;
}
List<SelectItem> selectCount = countSelectItem();
plainSelect.setSelectItems(selectCount);
sqlCount = selectStatement.toString();
} catch (Exception e) {
sqlCount = String.format(SqlUtils.SQL_BASE_COUNT, originalSql);
}
return sqlCount;
}
开发者ID:Caratacus,项目名称:mybatis-plus-mini,代码行数:33,代码来源:JsqlParserUtils.java
示例3: optimizeSql
import net.sf.jsqlparser.statement.select.Distinct; //导入依赖的package包/类
@Override
public SqlInfo optimizeSql(MetaObject metaObject, String sql) {
if (logger.isDebugEnabled()) {
logger.debug(" JsqlParserCountOptimize sql=" + sql);
}
SqlInfo sqlInfo = SqlInfo.newInstance();
try {
Select selectStatement = (Select) CCJSqlParserUtil.parse(sql);
PlainSelect plainSelect = (PlainSelect) selectStatement.getSelectBody();
Distinct distinct = plainSelect.getDistinct();
List<Expression> groupBy = plainSelect.getGroupByColumnReferences();
List<OrderByElement> orderBy = plainSelect.getOrderByElements();
// 添加包含groupBy 不去除orderBy
if (CollectionUtils.isEmpty(groupBy) && CollectionUtils.isNotEmpty(orderBy)) {
plainSelect.setOrderByElements(null);
sqlInfo.setOrderBy(false);
}
//#95 Github, selectItems contains #{} ${}, which will be translated to ?, and it may be in a function: power(#{myInt},2)
for (SelectItem item : plainSelect.getSelectItems()) {
if (item.toString().contains("?")) {
sqlInfo.setSql(String.format(SqlUtils.SQL_BASE_COUNT, selectStatement.toString()));
return sqlInfo;
}
}
// 包含 distinct、groupBy不优化
if (distinct != null || CollectionUtils.isNotEmpty(groupBy)) {
sqlInfo.setSql(String.format(SqlUtils.SQL_BASE_COUNT, selectStatement.toString()));
return sqlInfo;
}
// 优化 SQL
plainSelect.setSelectItems(countSelectItem);
sqlInfo.setSql(selectStatement.toString());
return sqlInfo;
} catch (Throwable e) {
// 无法优化使用原 SQL
sqlInfo.setSql(String.format(SqlUtils.SQL_BASE_COUNT, sql));
return sqlInfo;
}
}
开发者ID:baomidou,项目名称:mybatis-plus,代码行数:41,代码来源:JsqlParserCountOptimize.java
注:本文中的net.sf.jsqlparser.statement.select.Distinct类示例整理自Github/MSDocs等源码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。 |
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