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...
在Oracle SQL中,CASE表达式是一种条件表达式,用于根据不同的条件返回不同的结果。它可以在SELECT语句、WHERE子句、ORDER BY子句和其他SQL语句中使用。 CASE表达式有两种形式:简单CASE表达式和搜索CASE表达式。 简单CASE表达式: 简单CASE表达式使用固定的值进行比较,并根据每个值返回不同的结果。它的语法如下: ...
CASE expression syntax is similar to an IF-THEN-ELSE statement. Oracle checks each condition starting from the first condition (left to right). When a particular condition is satisfied (WHEN part) the expression returns the tagged value (THEN part). If none of the conditions are matched, the...
12 rows selected 与case when 配合: select case when grouping(e.department_id)=0 then ''||e.department_id else 'All Departments' end as department_id , case when grouping(e.job_id)=0 then e.job_id else 'All Jobs' end as job_id, avg(e.salary) from hr.employees e where e.depart...
oracle sql小结(主要讲横列转换的例子)decode 以及case,--建表createtablekecheng(idNUMBER,nameVARCHAR2(20),courseVARCHAR2(20),scoreNUMBER);--插入数据insertintokecheng(id,name,course,score)values
Oracle的CASE WHEN语法报ORA-00932错误 SELECT CASE WHEN dummy = 'x' THEN '-' ELSE 3 END FROM dual 1. 2. 3. 4. 5. 6. 上面SQL会报下面错误: ORA-00932: 数据类型不一致: 应为 CHAR, 但却获得 NUMBER 这是因为 THEN 后面是 CHAR 类型数据,而 ELSE 后面是 NUMBER 类型数据,数据类型不一致报错...
1、上表结果中的"sex"是用代码表示的,希望将代码用中文表示。可在语句中使用case语句: </>code SQL> select u.id,u.name,u.sex, (case u.sex when 1 then '男' when 2 then '女' else '空的' end )性别 from users u; ID NAME SEX 性别 ...
select sum(case when a.XX = '北京' then '1' else null end)from table a;补充'1' 这里可以是 1 或者'1'，但要求必须是数字才可以 。 否则就是无效的数字 字段
Introduction to SQL This tutorial provides an introduction to the Structured Query Language (SQL), learn how to create tables with primary keys, columns, constraints, indexes, and foreign keys. Tutorial SQL Macros - Creating parameterised views ...
gsql:Oracle_Functions.sql:1035: NOTICE: -- Function Test Result: gsql:Oracle_Functions.sql:1035: NOTICE: -- === gsql:Oracle_Functions.sql:1035: NOTICE: | result_type | case_count | start_time | complete_time | gsql:Oracle_Functions.sql:1035: NOTICE: |---|---|---|---|...