...例如 NOT IN、IS NOT NULL、NOT EXISTS,其中 NOT IN、NOT EXISTS 用于排除数据记录,应用在WHERE子句中较多;NOT EXISTS 也应用于创建数据库、数据表中使用较多...条件判断1 CASE表达式CASE表达式是一个比较常用的表达式工具,它允许在SQL语句中使用逻辑结构为 如果 ... 那么... 如果 ... 那么.
In other words, PL/SQL raises a CASE_NOT_FOUND error if you don’t specify an ELSE clause and the result of the CASE expression does not match any value in the WHEN clauses. Note that this behavior of the CASE statement is different from the IF THEN statement. When the IF THEN state...
Writingcaseexpressions directly in SQL statements is fine for one-off logic. Often you’ll want to reuse this logic in many queries. Copy-pasting it into every statement is error-prone and hard to maintain. You can avoid these problems by moving the logic into the table definition withvir...
resumable--enable or disable resumableforcurrentsession(DefaultFALSE)resumable_name--text string to help identify resumable statement resumable_timeout--waittime(inseconds)forRESUMABLE(Default7200)date_cache--size(inentries)ofdate conversioncache(Default1000)no_index_errors--abort load on any indexerrors...
This Oracle WHERE clause example uses the WHERE clause to define multiple conditions, but instead of using the AND condition, it uses the OR condition. In this case, this SELECT statement would return all supplier_id values where the supplier_name is Apple or Microsoft.Example...
You can use aCASEexpression in any statement or clause that accepts a valid expression. For example, you can use theCASEexpression in statements such asSELECT,UPDATE, orDELETE, and in clauses likeSELECT,WHERE,HAVING, andORDER BY. TheCASEexpression has two forms: ...
--声明游标;CURSOR cursor_name IS select_statement--For 循环游标--(1)定义游标--(2)定义游标变量--(3)使用for循环来使用这个游标 declare--类型定义 cursor c_jobisselectempno,ename,job,salfromempwherejob='MANAGER';--定义一个游标变量c_row c_job%ROWTYPE,该类型为游标c_job中的一行数据类型 ...
Oracle中带CASE语句的条件WHERE子句可以将where子句编写为：
where af.appid=aid and af.foundationid=fid;-- 没有into,编译报错,提示:Compilation Error: PLS-00428: an INTO clause is expected in this SELECT statement 3.在利用select…into…语法时,必须先确保数据库中有该条记录,否则会报出”no data found”异常。 可以在该语法之前,先利用select count(*) from...
MERGEstatement added. Support of new datetime types and conversion of records and collections as CLR data types added. Added new features of Tester. Tables now can be tested as objects using Tester, a call order of several testable objects in test case can be altered, user can test procedures...