SELECT with a variable Tablename

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SELECT with a variable Tablename

bgrossnickle

Ten Centuries

Points: 1332
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August 13, 2013 at 12:22 pm

#276154

I am rying to run a TSQL SELECT Count(*) that has a @Tablename variable in it.
My Tablename name needs to be variable and I will build it on the fly. All I want to know if if there is data in the table.
--Tried this but it did not work because of the @Database
Declare @Database varchar(20)
Set @Database = 'TDSTEP'
Declare @RowCount int
SELECT @RowCount = Count(*) FROM @Database
Print @RowCount
--Tried this but it did not work because of the @RowCount
Declare @Database varchar(20)
Set @Database = 'TDSTEP'
Declare @RowCount int
declare @sql as varchar(max)
set @sql = 'SELECT @RowCount = Count(*) FROM ' + @Database
exec (@SQL)
How can i get a variable TableName and yet interigate the number of rows returned?

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Sean Lange SSC Guru Points: 286590 More actions · Answer 1

bgrossnickle (8/13/2013)
I am rying to run a TSQL SELECT Count(*) that has a @Tablename variable in it.
My Tablename name needs to be variable and I will build it on the fly. All I want to know if if there is data in the table.
--Tried this but it did not work because of the @Database
Declare @Database varchar(20)
Set @Database = 'TDSTEP'
Declare @RowCount int
SELECT @RowCount = Count(*) FROM @Database
Print @RowCount
--Tried this but it did not work because of the @RowCount
Declare @Database varchar(20)
Set @Database = 'TDSTEP'
Declare @RowCount int
declare @sql as varchar(max)
set @sql = 'SELECT @RowCount = Count(*) FROM ' + @Database
exec (@SQL)
How can i get a variable TableName and yet interigate the number of rows returned?

Do you need this to use a variable for some reason?

You can do this with something like this.

Declare @Database varchar(20)

Set @Database = 'YourTableNameHere'

Declare @RowCount int

declare @sql as varchar(max)

set @sql = 'SELECT Count(*) FROM ' + @Database

declare @MyCount table(MyRowCount int)

insert @MyCount

exec (@SQL)

select * from @MyCount

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Bill Talada SSChampion Points: 11954 More actions · Answer 2

declare @TableName varchar(128);

set @TableName = 'sysdiagrams';

if exists

(

select i.rowcnt

from sys.tables t

join sys.sysindexes i on t.object_id = i.id

where indid in (1,0)

and t.name = @TableName

)

print 'yes'

;

Luis Cazares SSC Guru Points: 183706 More actions · Answer 3

Have you tried something like this?

Declare @Database varchar(20)

Set @Database = 'TDSTEP'

Declare @RowCount int

declare @sql as nvarchar(max)

set @sql = ' SELECT @RowCountOUT = Count(*) FROM ' + @Database

exec sp_executesql @sql, N'@RowCountOUT int OUTPUT', @RowCountOUT=@RowCount OUTPUT;

SELECT @RowCount

Luis C.
General Disclaimer:
Are you seriously taking the advice and code from someone from the internet without testing it? Do you at least understand it? Or can it easily kill your server?

How to post data/code on a forum to get the best help: Option 1 / Option 2

bgrossnickle Ten Centuries Points: 1332 More actions · Answer 4

FYI - I wanted the FROM @tablename to be a variable. Not a variable in the WHERE clause.

Luis Cazares SSC Guru Points: 183706 More actions · Answer 5

bgrossnickle (8/13/2013)
FYI - I wanted the FROM @tablename to be a variable. Not a variable in the WHERE clause.

But you got a different way of doing things that will give you what you need.

Luis C.
General Disclaimer:
Are you seriously taking the advice and code from someone from the internet without testing it? Do you at least understand it? Or can it easily kill your server?

How to post data/code on a forum to get the best help: Option 1 / Option 2

bgrossnickle Ten Centuries Points: 1332 More actions · Answer 6

bgrossnickle

Ten Centuries

Points: 1332

August 13, 2013 at 6:40 pm

#1641193

Both Sean and Luis code worked great. thanks.

Dwain Camps SSC Guru Points: 86948 More actions · Answer 7

Could you use something like this?

USE [TDStep]

GO

SELECT TableName=OBJECT_NAME(OBJECT_ID), st.row_count

FROM sys.dm_db_partition_stats st

WHERE index_id < 2

ORDER BY st.row_count DESC

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