mysql - 如何在mysql中使用if语句将文本添加到字符串值

Question

我想检查schoolid是否为1，然后在record.year中以两位数的形式添加下一年的连字符

例如，如果 record.year = 1997，且 schools.schoolid =1，那么我希望 record.year 返回 1997-98。

$sqlquery = 'SELECT 
        record.year, 
        schools.school, 
        schools.schoolid, 
        sports.sport, 
        conferences.conference, 
        record.year 
    FROM 
        `record`,
        `schools`,
        `conferences`, 
        `sports` 
    WHERE 
        schools.schoolid = record.schoolid 
    AND 
        sports.sportid = record.sportid 
    AND 
        record.conferenceid = conferences.conferenceid';    

Answer 1

假设record.year是INT类型，

SELECT    
IF
(
   schools.schoolid = 1,
   CONCAT(record.year,'-',RIGHT(record.year+1,2)),
   record.year
) AS year,
schools.school,
....

如果 record.year 是 varchar 在添加连字符时将其转换为数字:

SELECT    
IF
(
   schools.schoolid = 1,
   CONCAT(record.year,'-',RIGHT(CAST(record.year AS SIGNED)+1,2)),
   record.year
) AS year,
schools.school,
....