獲取特定約束的最後一個插入值

Question

我需要獲取m_id = 2的最後一個插入值。我有兩個記錄M_ID = 2，具有ID作爲其主鍵，我需要得到max(id)爲m_id=2

如

ID M_ID MNAME

2 2樣品

3 2 SAMPLE1

我只需要提取Id=3的記錄。我需要檢查以下查詢的MAX（id）

select a.*,b.MName,b.ZipCode,b.City,b.Address,b.email from insurance_details as a,insmemberdetails as b where b.id='2' and a.m_id='2' 

Answer 1

使用ORDER BY ID DESC和LIMIT 1：

select a.*,b.MName,b.ZipCode,b.City,b.Address,b.email 
from insurance_details as a,insmemberdetails as b 
where b.id='2' and a.m_id='2' 
order by b.id desc 
limit 1 

Answer 2

您可以使用它像這樣：

select a.*,b.MName,b.ZipCode,b.City,b.Address,b.email 
from insurance_details as a,insmemberdetails as b 
where a.m_id='2' order by b.id desc limit 1 

您也可以使用這樣的：

select a.*,b.MName,b.ZipCode,b.City,b.Address,b.email 
from insurance_details as a,insmemberdetails as b 
where b.id= (SELECT MAX(id) FROM b) and a.m_id='2' 

Answer 3

試試這個查詢： -

select a.*,b.MName,b.ZipCode,b.City,b.Address,b.email 
from insurance_details as a,insmemberdetails as b 
where b.id='2' and 
m_id = (SELECT MAX(m_id) FROM insurance_details) 

希望它能幫助你:-)