SQl if where子句中的语句

Question

如何在我的陈述中添加底线？

SELECT
AgentID,
PaymentAmount
FROM Table A

WHERE 
DATEOFPAYMENT 

GROUP BY 
CollectorNumber

ORDER BY 
CollectorNumber,
LastName,
DateofPayment,
PaymentAmount

---

  

如果DATEOFPAYMENT =昨天，那么PaymentAmount else 0为＆＃39;前一天＆＃39;

或

  

如果DATEOFPAYMENT = current_Month，那么PaymentAmount else 0为＆＃39; MTD＆＃39;

或

  

如果DATEOFPAYMENT = current_Year则PaymentAmount else 0为＆＃39; YTD

Answer 1

我们可以研究CASE syntax from here , it would be, roughly (I am not acquainted with MySQL date formats , so please look that up )

SELECT AgentID, PaymentAmount FROM Table A

WHERE CASE DATEOFPAYMENT 
 WHEN subdate(currentDate, 1)  THEN PaymentAmount  
 WHEN month() THEN PaymentAmount 
 WHEN year()  THEN PaymentAmount 
 ELSE 0
END

GROUP BY CollectorNumber

ORDER BY CollectorNumber, LastName, DateofPayment,
PaymentAmount

这几乎是伪代码，所以请修改语法。但案例陈述是这样的。