SQL Server: If @variable is null set @variable = x

if-statement, sql-server, stored-procedures

Solution

Use IS NULL to check instead, e.g.:

IF (@start IS NULL)
   SET @start = '20130101'

Or, in one line:

SET @start = ISNULL(@start, '20130101')

Update: Also, you are setting @week too soon:

declare @week datetime = DATEADD(DAY, 6, @start) -- @start is NULL

change to:

declare @week datetime
-- IF checks here to set @start/@end if null...
SET @week = DATEADD(DAY, 6, @start)

On a side note, also worth refactoring your loop to set-based approach for performance. A tally/numbers table type approach is an option to research.

Problem

I am using SQL Server. I want it so if @variable is null, it is set to some value. ``` set nocount on IF object_id('tempdb..##tmp') IS NOT NULL BEGIN DROP TABLE ##tmp END CREATE TABLE ##tmp (week varchar (25), users int, stamps int) declare @inter varchar(100) declare @qt_users int declare @qt_stamps int declare @comando varchar(5000) declare @start date = null declare @end date = null declare @week datetime = DATEADD(DAY, 6, @start) --if @start is null, set it to a value: if (null!=@start) begin set @start = '20130101' end if (null!=@end) begin set @end = GETDATE() end while @start < @end begin select @qt_users = COUNT(distinct id_user) from stamps where dt_synchronization between @start and @week select @qt_stamps = COUNT(id_stamp) from stamps where dt_synchronization between @start and @week set @inter = convert(varchar(10),@start,105) + ' até ' + convert(varchar(10),@week,105) set @comando = 'insert into ##tmp(week, users, stamps) values (''' + @inter + ''','''+ cast(@qt_users as varchar) + ''',''' + cast(@qt_stamps as varchar) + ''')' exec (@comando) set @start = @week + 1 set @week = dateadd(day, 6, @start) end select week, users, stamps from ##tmp ```

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