This is called Deep Autoexists, because the Top10SellingProducts set is evaluated to meet the slicing conditions of the query. Deep Autoexists means that all expressions will be evaluated to meet the deepest possible space after applying the slicer expressions, the sub select expressions in the ...
Besides, in the hierarchical query, the search is performed strictly according to the depth-first order. If ROWNUM is used as the filtering condition in START WITH or CONNECT BY, the value of ROWNUM is increased by 1 for each record to be returned. Then, the record is verified based on ...
美 英 un.选择语句 网络章和第七章查询句;选择叙述;选择指令 英汉 网络释义 un. 1. 选择语句
(1)语法解析阶段,能够在select语句中识别新增的ROTATE关键字,并对其功能子句进行匹配,进行语法解析,生成正确的语法解析树。(2)子计划生成阶段,通过解析语法解析树,对于ROTATE子句生成为查询树的子查询,对于NOT ROTATE子句生成为一个union all语句的查询树。 【资料修改pr链接】: https://gitee.com/opengauss/docs/...
"About SQL Expressions "for the syntax ofexpr Restrictions on the Select List If you also specify agroup_by_clausein this statement, then this select list can contain only the following types of expressions: Constants Aggregate functions and the functionsUSER,UID, andSYSDATE ...
MySQL permits duplicate column names. That is, there can be more than oneselect_exprwith the same name. This is an extension to standard SQL. Because MySQL also permitsGROUP BYandHAVINGto refer toselect_exprvalues, this can result in an ambiguity: ...
Forces the Microsoft SQL Server database to use a nested-loop algorithm to process a particular SQL statement containing a join algorithm. This means that a record from the first table is fetched before any records from the second table are fetched. Typically, other join algorithms, such as ha...
【测试类型:SQL功能】 3.0.1 从库COUNT结果与主库不一致,与SELECT 返回条数不一致 M【测试版本:3.0.1 】 问题描述【测试环境】单机/1主x备x级联备: 1主3从【版本及...
SQL_BIG_RESULT can be used with GROUP BY or DISTINCT to tell the optimiser that the result set will have many rows. In this case, MySQL will directly use disk-based temporary tables if needed. MySQL will also, in this case, prefer sorting to doing a temporary table with a key on the...
component for the client field, which means that a client column is added to the results set here implicitly. If the client field is accessed explicitly or implicitly in theSELECTstatement, an additionentity~clntmust be used to give the field a name that can be used in the current statement...