Sql – Using EXEC inside SELECT statement in SQL Server

sqlsql-server

I need to use exec inside of select clause. The query for the exec is created according to the columns of the table to on which select clause if used. What i want to do is something like following:

 SELECT distinct 
     MTMain.[TableName],
     MTMain.[TableFKey], 
     (select IsActive (exec GetStringForIsActive MTMain.[TableName],MTMain.[TableFKey]))
 FROM
     [MasterTableForLanguage] MTMain

Here, GetStringForIsActive is the stored procedure I want to execute for every row selected from MasterTableForLanguage.
The stored procedure will use EXEC to execute the following string

select IsActive from [TableName] where PKID= cast([TableFKey] as int)

TableName and TableFKey will be inputs of the stored procedure.

Best Solution

If you can modify your Stored Procedure GetStringForIsActive to return TableName, TableFKey and IsActive, you can use a cursor to get execute it for each row and add the results to a temp table.

ie:

exec GetStringForIsActive 'TableName', 'TableFKey'
returns
select [TableName], [TableFKey], IsActive from [TableName] where PKID= cast([TableFKey] as int)

The code would be like this:

declare @TableName nvarchar(50)
declare @TableFKey nvarchar(50)
declare @Results table (TableName nvarchar(50), TableFKey nvarchar(50), IsActive bit)

declare TableCursor cursor fast_forward for
   select TableName, TableFKey from MasterTableForLanguage

open TableCursor

fetch next from TableCursor into @TableName, @TableFKey

if @@FETCH_STATUS <> -1
   print 'MasterTableForLanguage check'

while (@@FETCH_STATUS <> -1)
begin


   insert into @Results
   exec GetStringForIsActive @TableName, @TableFKey

   fetch next from TableCursor into @TableName, @TableFKey

end
close TaleCursor
deallocate TableCursor

select * from @Results

Related Solutions

Sql – How to perform an IF…THEN in an SQL SELECT

The CASE statement is the closest to IF in SQL and is supported on all versions of SQL Server.

SELECT CAST(
             CASE
                  WHEN Obsolete = 'N' or InStock = 'Y'
                     THEN 1
                  ELSE 0
             END AS bit) as Saleable, *
FROM Product

You only need to use the CAST operator if you want the result as a Boolean value. If you are happy with an int, this works:

SELECT CASE
            WHEN Obsolete = 'N' or InStock = 'Y'
               THEN 1
               ELSE 0
       END as Saleable, *
FROM Product

CASE statements can be embedded in other CASE statements and even included in aggregates.

SQL Server Denali (SQL Server 2012) adds the IIF statement which is also available in access (pointed out by Martin Smith):

SELECT IIF(Obsolete = 'N' or InStock = 'Y', 1, 0) as Saleable, * FROM Product

Sql – Add a column with a default value to an existing table in SQL Server

Syntax:

ALTER TABLE {TABLENAME} 
ADD {COLUMNNAME} {TYPE} {NULL|NOT NULL} 
CONSTRAINT {CONSTRAINT_NAME} DEFAULT {DEFAULT_VALUE}
WITH VALUES

Example:

ALTER TABLE SomeTable
        ADD SomeCol Bit NULL --Or NOT NULL.
 CONSTRAINT D_SomeTable_SomeCol --When Omitted a Default-Constraint Name is autogenerated.
    DEFAULT (0)--Optional Default-Constraint.
WITH VALUES --Add if Column is Nullable and you want the Default Value for Existing Records.

Notes:

Optional Constraint Name:
If you leave out CONSTRAINT D_SomeTable_SomeCol then SQL Server will autogenerate
a Default-Contraint with a funny Name like: DF__SomeTa__SomeC__4FB7FEF6

Optional With-Values Statement:
The WITH VALUES is only needed when your Column is Nullable
and you want the Default Value used for Existing Records.
If your Column is NOT NULL, then it will automatically use the Default Value
for all Existing Records, whether you specify WITH VALUES or not.

How Inserts work with a Default-Constraint:
If you insert a Record into SomeTable and do not Specify SomeCol's value, then it will Default to 0.
If you insert a Record and Specify SomeCol's value as NULL (and your column allows nulls),
then the Default-Constraint will not be used and NULL will be inserted as the Value.

Notes were based on everyone's great feedback below.
Special Thanks to:
@Yatrix, @WalterStabosz, @YahooSerious, and @StackMan for their Comments.