SQL>show userUSER为"HR"SQL>SELECTfirst_name,last_name,department_id,2CASEdepartment_id3WHEN10THEN'Accounting'4WHEN20THEN'Sales'5WHEN30THEN'Finance'6ELSE'Other'7ENDdepartment_name8FROMemployees where rownum<2;FIRST_NAMELAST_NAMEDEPARTMENT_IDDEPARTMENT_NAME---Steven King90OtherSQL> ※测试使用的Orac...
CASE expression perform if-then-else logic in SQL without having to use PL/SQL. CASE works in a similar manner to DECODE(). CASE is ANSI-compliant. There are two types of CASE expressions: Simple case expressions use expressions to determine the returned value. Searched case expressions use ...
WHEN price IS NULL THEN 'Unpriced' WHEN price < 10 THEN 'Bargain' WHEN price BETWEEN 10 and 20 THEN 'Average' ELSE 'Gift to impress relatives' END, Title ORDER BY CASE WHEN price IS NULL THEN 'Unpriced' WHEN price < 10 THEN 'Bargain' WHEN price BETWEEN 10 and 20 THEN 'Average' EL...
expression_n:第n个WHEN子句中的表达式,它通常也是一个常量,当选择器的值等于该表达式的值时,程序将执行plsql_sentence_n语句。 plsql_sentence:一个PL/SQL语句,当没有与选择器匹配的WHEN常量时,程序将执行该PL/SQL语句,其所在的ELSE语句是一个可选项。 首先指定一个季度数值,然后使用CASE语句判断它所包含的月份...
DECODE is considered the most powerful function in Oracle. Oracle 8i release introduced the CASE expression. The CASE expression can do all that DECODE does plus lot of other things including IF-THEN analysis, use of any comparison operator and checking multiple conditions, all in a SQL query ...
06oracle之条件表达式(case、decode)、多行函数、嵌套函数、分组子句的要求、Where和having的选择,条件表达式:条件表达式的作用是:在SQL语句中使用判断的逻辑(类似于IF-THEN-ELSE)来呈现个性化的数据。条件判断语句有两种:
CASE是Oracle SQL中的一种条件表达式,它允许根据给定的条件选择不同的操作或返回不同的结果。通常,在SELECT语句中使用CASE来执行条件判断并返回相应的结果。 基本语法如下: ``` CASE WHEN condition1 THEN result1 WHEN condition2 THEN result2 ...
case when a.字段!=null && b.字段!=null then '好蛋疼的问题' then ... else ... end &&是与操作 你
oracle的case语句oracle的case语句 Oracle的CASE语句是SQL中常用的条件语句之一,它允许用户根据特定的条件在查询结果中执行更复杂的操作。下面是关于Oracle的CASE语句的详细介绍。 1. CASE语句的基本用法 在Oracle中,用户可以使用CASE语句来根据某种条件执行不同的操作,使用方式如下:...
PLSQL 简单case语句 1 简单的case语句会给出一个表达式，并将可能发生的结果与其做比较，如果匹配成功则执行对应的语句 2 语法：[ <<lable_name>> ]CASE case_operandWHEN when_operand1 THEN statement1;[WHEN when_operand2 THENstatement1;] ...[ELSEstatementN]END CASE [ lable_name ];3 说明：<<labl...