SQL 2005 Can I use keyword like in a case statemen

问题:

I need a case statement that allows partial matches. I get a syntax error, but am wondering if anything similar to this is possible. If not, my secondary solution is to re-write as a cursor... Example:

SELECT CASE ColumnName
           WHEN 'value1' THEN 'answer1'
           WHEN 'value2' THEN 'answer2'
           WHEN LIKE '%TEST%' THEN 'answer3'
       END AS Answer
FROM TableName

回答1:

try this

SELECT CASE 
           WHEN ColumnName = 'value1' THEN 'answer1'
           WHEN ColumnName = 'value2' THEN 'answer2'
           WHEN ColumnName LIKE '%TEST%' THEN 'answer3'
       END AS Answer
FROM TableName

example you can run

SELECT name,CASE 
           WHEN Name = 'sysobjects' THEN 'answer1'
           WHEN Name = 'syscols' THEN 'answer2'
           WHEN Name LIKE '%p%' THEN 'answer3'
           ELSE 'unknown'
       END AS Answer
FROM sysobjects

回答2:

Need to use a slightly different CASE syntax:

SELECT CASE WHEN ColumnName LIKE 'value1' THEN 'answer1'
            WHEN ColumnName LIKE 'value2' THEN 'answer2'
            WHEN ColumnName LIKE '%TEST%' THEN 'answer3'
ELSE 'not like any of them' END [Answer]
FROM TableName

回答3:

Alternatively, you can nest CASE condition and CASE WHEN value clauses, like so:

SELECT CASE ColumnName
           WHEN 'value1' THEN 'answer1'
           WHEN 'value2' THEN 'answer2'
           ELSE CASE WHEN ColumnName LIKE '%TEST%' THEN 'answer3' END
       END AS Answer
FROM TableName

回答4:

You are using the "simple CASE expression" but you should be using the "searched CASE expression". See the documentation for some examples.

回答5:

In sql ORACLE 10

SELECT 
    CASE WHEN instr(ColumnName, 'value1')>0 THEN 'answer1'
       WHEN instr(ColumnName,'value2')>0 THEN 'answer2'
       WHEN instr(ColumnName,'TEST')>0 THEN 'answer3'
       ELSE 'not like any of them' 
    END
FROM TableName