the single correlated reference is the occurrence of X.WORKDEPT in the subselect's FROM clause. Here, the qualifierXis the correlation name defined in the FROM clause of the outer SELECT statement. In that claus
SQL first evaluates the subquery and then substitutes the result in the WHERE clause of the SELECT statement. In this example, the result is the company-wide average educational level. Besides returning a single row, a subquery can return no rows. If it does, the result of the compare is ...
db1 包含 table1,table2db2 包含 table1,table3 这是允许的,可以用 db1.table1, db2.table1 这样来表示 学习时间:0.5天 坑1:DROP 操作极其危险,也就是平时我们听到的删库跑路操作,一般情况不要用。 ￥第7关,函数使用帮我解决难题 在SQL运用的高级阶段,往往用到各种函数,查询条件里可以用函数,数据结果的...
db2 IBM DB2 8.x and greater db2iSeries IBM DB2 for iSeries/i5, V5R4 and greater firebirdsql Firebird 2.5 and greater informix Informix 11.5 and greater sqlserver Microsoft SQL Server 2000 and greater mysql MySQL 3.2.x and greater mariadb MariaDB 5.1 and greater oracle Oracle 8.0.5, 8i and...
数据库关键字 (Oracle, SQL Server, DB2) Oracle SQL Server DB2 ! @@IDENTITY DETERMINISTIC & ADD DISALLOW ( ALL DISCONNECT ) ALTER DISTINCT * AND DO + ANY DOUBLE , AS DROP - ASC DSNHATTR . AUTHORIZATION DSSIZE / AVG DYNAMIC : BACKUP EACH < BEGIN EDITPROC << BETWEEN ...
(%s)"/><comment query="-- -"query2="/*"query3="#"/><substring query="MID((%s),%d,%d)"/><concatenate query="CONCAT(%s,%s)"/><casequery="SELECT (CASE WHEN (%s) THEN 1 ELSE 0 END)"/><hex query="HEX(%s)"/><inference query="ORD(MID((%s),%d,1))>%d"/><banner query=...
BigQuery 2025-05-02Db2 (LUW) 12.1aMariaDB 11.7MySQL 9.3.0Oracle DB 23.8aPostgreSQL 17SQL Server 2022SQLite 3.49.0aThree-valued logicF571: Boolean testtrue, false outside of is No is unknown. Is null can be used for this purpose
Listing of SQLSTATE valuesThe tables below provide descriptions of SQLSTATE codes that can be returned to applications by DB2® UDB for iSeries™.
Session C connects to another database in Azure SQL Database testdb2 and wants to access ##test created in testdb1. This select fails due to the database scope for the global temp tables SQL Copy SELECT * FROM ##test; Which generates the following error: Output Copy Msg 208, Level...
CASE statement with substring CASE WHEN - Adding collate into it. Case WHEN and concatenate string CASE WHEN isnumeric(ColValue) THEN ... ELSE ... END CASE WHEN MIN,SUM ETC. CASE WHEN Problem with CASE NULL cast nvarchar to smalldatetime Cast a varchar(6), 112 as date CAST and IsNull...