SQL日期大于X

Question

I am trying to run the query;

SELECT PO_PurchaseOrderDetail.ItemCodeDesc,   
       PO_PurchaseOrderDetail.QuantityOrdered, 
       PO_PurchaseOrderDetail.QuantityReceived, 
        PO_PurchaseOrderDetail.UnitCost, 
       PO_PurchaseOrderDetail.JT158_WTSalesOrderNo, 
       PO_PurchaseOrderDetail.PurchaseOrderNo, 
       PO_PurchaseOrderHeader.PurchaseName, 
       PO_PurchaseOrderHeader.PurchaseOrderDate
FROM PO_PurchaseOrderDetail PO_PurchaseOrderDetail, PO_PurchaseOrderHeader PO_PurchaseOrderHeader
WHERE (PO_PurchaseOrderDetail.PurchaseOrderNo=PO_PurchaseOrderHeader.PurchaseOrderNo) 
AND ***(PO_PurchaseOrderHeader.PurchaseOrderDate > '2013-12-31')***
ORDER BY PO_PurchaseOrderDetail.JT158_WTSalesOrderNo, PO_PurchaseOrderDetail.PurchaseOrderNo

My problem is, that the date is stored in the YYYY-MM-DD format. I need to only show data after a certain date. So, because 2013-12-31 is a string rather than a number, the operator > doesn't work. Any ideas?

Answer 1

Try to CAST string as DATE in following:

PS if PurchaseOrderDate is not DATE datatype you could also CAST It: CAST(PO_PurchaseOrderHeader.PurchaseOrderDate AS DATE)

SELECT PO_PurchaseOrderDetail.ItemCodeDesc,
       PO_PurchaseOrderDetail.QuantityOrdered,
       PO_PurchaseOrderDetail.QuantityReceived, 
       PO_PurchaseOrderDetail.UnitCost, 
       PO_PurchaseOrderDetail.JT158_WTSalesOrderNo, 
       PO_PurchaseOrderDetail.PurchaseOrderNo, 
       PO_PurchaseOrderHeader.PurchaseName, 
       PO_PurchaseOrderHeader.PurchaseOrderDate
FROM   PO_PurchaseOrderDetail PO_PurchaseOrderDetail, 
       PO_PurchaseOrderHeader PO_PurchaseOrderHeader
WHERE  PO_PurchaseOrderDetail.PurchaseOrderNo = PO_PurchaseOrderHeader.PurchaseOrderNo AND    
       PO_PurchaseOrderHeader.PurchaseOrderDate > CAST('2013-12-31' AS DATE)
ORDER BY PO_PurchaseOrderDetail.JT158_WTSalesOrderNo, 
         PO_PurchaseOrderDetail.PurchaseOrderNo