相当于是sql查询中的sql片段 with score as (SELECT * FROM [ZhaoxiEdu].[dbo].[ScoreInfo]) select * from score where [name] ='张三' 1. 2.10、子查询 / exists关键字查询 #子查询 SELECT * FROM [ZhaoxiEdu].[dbo].[ScoreInfo] where id in (SELECT Id FROM [ZhaoxiEdu].[dbo].[ScoreInfo...
除了WITH子句之外,Oracle SQL中还有一种常用的查询方式是子查询。子查询可以帮助用户在查询中嵌套使用多个SELECT语句,以便更好地筛选和管理数据。 例如,以下是一个使用子查询的查询示例: SELECT * FROM table1 WHERE column1 IN ( SELECT column1 FROM table2 ...
Oracle PL/SQL之WITH查询 [转自] http://blog.csdn.net/t0nsha/article/details/6730855 为什么要用WITH? 1. 如果需要在一段复杂查询里多次应用同一个查询,用WITH可实现代码重用; 2. WITH查询类似将查询结果保留到用户临时表里,在大的复杂查询中可以减少IO,有一定的性能优化作用。 WITH查询有何限制与特性? 1...
Oracle管道函数是一种特殊的函数,它可以在SQL查询中使用WITH子句来创建临时表,并将结果作为表返回。这种函数可以用于处理大量数据,并且可以提高查询的性能和灵活性。 使用WITH子句的SQL的Oracle管道函数的语法如下: 代码语言:txt 复制 CREATE OR REPLACE FUNCTION function_name (parameters) RETURN return_type PIPELINED...
4 . Download and unzip the files.zip to a local folder on your file system. In this tutorial, we use the C:\sqldev3.0 folder. Creating a Database ConnectionThe first step to managing database objects using Oracle SQL Developer 3.0 is to create a database connection. Perform the ...
1.3 Starting and Leaving SQLcl Use the following commands to log in to and out of SQLcl. SQLCL [[option] [logon | / NOLOG] [start]] where option has the following syntax: -H[ELP] | -V[ERSION] | [ [-C[OMPATIBILITY] x.y[.z]]] [-L[OGON]] [-NOLOGINTIME] [-R[E...
https://github.com/dongxuyang1985/sql_in_action -- Oracle WITHtransfer (start_station, stop_station, stops, path)AS( SELECTstation_name, next_station,1, line_name||station_name||'->'||line_name||next_station FROMbj_subwayWHEREstation_name='王府井' ...
Oracle SQL Developer is a tool. Google Definition of ‘tool’ My general rule for using tools boils down to – if the tool is making it harder to do the job you’re using it for, you’re either ‘doing it wrong’ or you have the wrong tool. ...
with 子句是在oracle 9i release 2 中引入的。with 子句又叫做子查询构造语句。可以用来给一个子查询块命名。 该查询块的检索结果会被oracle 保存在用户的临时表空间中,该命名块就像虚表或者内联视图一样。 语法 代码语言:javascript 复制 WITHsubquery_nameAS(the aggregationSQLstatement)SELECT(query naming subquery...
Autonomous Database has rich support for using Oracle SQL to query data that is stored outside of the database. This data may be available in other databases, object stores or thru REST endpoints. The implication is that ADB's SQL access capability can dramatically simplify your data architectu...