Level Extreme platform
Subscription
Corporate profile
Products & Services
Support
Legal
Français
Using CASE in JOIN expression
Message
 
General information
Forum:
Microsoft SQL Server
Category:
SQL syntax
Environment versions
SQL Server:
SQL Server 2005
Miscellaneous
Thread ID:
01411536
Message ID:
01411546
Views:
23
>>Hi,
>>
>>I am building a SQL Command expression (to be used from VFP 9 application) where the JOIN is an expression.
>>
>>When I use the expression with IIF() for VFP data it works. Here is my VFP expression
>>
>>
>>cJoinExpr = "JOIN TABLE1 ON IIF(TABLE2.ORDER_NO>0,TABLE2.ID_FLD = 
>> TABLE1.ID_FLD, TABLE3.ID_FLD = TABLE1.ID_FLD) "
>>
>>
>>But when I change the expression to be used against SQL Server I get error. Here is my expression for SQL Server:
>>
>>
>>cJoinExpr = "JOIN TABLE1 ON CASE WHEN TABLE2.ORDER_NO>0 THEN TABLE2.ID_FLD =
>> TABLE1.ID_FLD ELSE TABLE3.ID_FLD = TABLE1.ID_FLD END "
>>
>>
>>What is wrong with my second (SQL Server) expression?
>
>I don't think you can make it work this way. Simply use two separate JOINS with a UNION, e.g. JOIN with the table based on the field and condition and then UNION with join based on another field with WHERE.
>
>Alternatively you can do
>
>JOIN TABLE1 ON (Table2.Order_NO > 0 and Table2.ID_Field = ..) OR (....)
Thank you for your input.
"The creative process is nothing but a series of crises." Isaac Bashevis Singer
"My experience is that as soon as people are old enough to know better, they don't know anything at all." Oscar Wilde
"If a nation values anything more than freedom, it will lose its freedom; and the irony of it is that if it is comfort or money that it values more, it will lose that too." W.Somerset Maugham
Previous
Next
Reply
Map
View

Click here to load this message in the networking platform