How do I find out how many tables are on my instance of SQL Server? I can get it for a single schema using select count(*) from sysobjects where type = 'U'
(from how to count number of tables/views/index in my database)
You're using the word "schema", but I think you're really asking to count tables across all "databases".
declare #t table (
DBName sysname,
NumTables int
)
insert into #t
exec sp_MSforeachdb N'select ''?'', count(*)
from [?].dbo.sysobjects
where type = ''U'''
select DBName, NumTables
from #t
where DBName not in ('distribution','master','model','msdb','tempdb')
order by DBName
select SUM(NumTables) as TotalTables
from #t
where DBName not in ('distribution','master','model','msdb','tempdb')
An option without using the hidden, undocumented sp_MSforeachdb
declare #sql nvarchar(max)
select #sql = coalesce(#sql + ' + ', '') + REPLACE('
(select count(*)
from ::DB::.sys.objects
where is_ms_shipped = 0
and type_desc = ''USER_TABLE'')', '::DB::', QUOTENAME(name))
from master.sys.databases
where owner_sid != 0x01
select #sql = 'select ' + #sql
exec (#sql) -- returns a single count of all [user] tables in the instance
>
A note on performance. It is insignificant in the greater scheme of things, but with all things interesting, someone is bound to time it. Here is a comparison of the ms_foreachdb approach passing through a temp table (it internally uses a cursor) against the string-concat method.
-- all the variables that we will use
declare #i int -- loop variable
declare #sql nvarchar(max) -- statement var used for 1st approach
declare #t table (DBName sysname, NumTables int) -- table used for 2nd approach
-- init plan cache and buffers
dbcc freeproccache dbcc dropcleanbuffers
print convert(varchar(30), getdate(), 121)
set #i = 0 while #i < 5 begin
set #sql = null
select #sql = coalesce(#sql, '') + REPLACE('
select #c = #c + count(*)
from ::DB::.sys.objects
where is_ms_shipped = 0
and type_desc = ''USER_TABLE''', '::DB::', QUOTENAME(name))
from master.sys.databases
where owner_sid != 0x01
select #sql = 'set nocount on declare #c int set #c = 0 ' + #sql + ' select #c'
exec (#sql)
-- clear plan cache and buffers after each run
dbcc freeproccache dbcc dropcleanbuffers set #i = #i + 1
end
print convert(varchar(30), getdate(), 121)
set #i = 0 while #i < 5 begin
insert into #t
exec sp_MSforeachdb N'select ''?'', count(*)
from [?].dbo.sysobjects
where type = ''U'''
select SUM(NumTables) as TotalTables
from #t
where DBName not in ('distribution','master','model','msdb','tempdb')
-- unfortunately this is required
delete from #t
-- clear plan cache and buffers after each run
dbcc freeproccache dbcc dropcleanbuffers set #i = #i + 1
end
print convert(varchar(30), getdate(), 121)
The result obtained for only 5 invocations (loop iterations) of each. YMMV
start : 2011-01-21 14:21:45.180
end of string-concat : 2011-01-21 14:21:57.497 (12.317)
end of sp_msforeachdb : 2011-01-21 14:22:13.937 (16.440)
It has to be noted that the temp table has to be emptied between each iteration of the 2nd approach, so that could contribute to the total time. It should have been insignificant though
Here is an answer that does not use undocumented functions and works in SQL Server 2005, 2008 and 2008R2. This answer can be used with minor modifications to run any statement across databases.
DECLARE #sql varchar(200), #dbname sysname, #dbid smallint;
CREATE table #alltables
(dbname sysname,
[number of tables] int);
SELECT top 1 #dbname = name, #dbid = database_id
FROM sys.databases
where database_id > 4;
WHILE (#dbname is not null)
begin
-- the statement below could contain any valid select statement
set #sql = 'use ' + #dbname + '; insert into #alltables select ''' + #dbname + ''', count(*) from sys.tables';
EXEC (#sql)
set #dbname = null;
SELECT top 1 #dbname = name, #dbid = database_id
FROM sys.databases
where database_id > #dbid;
end;
select * FROM #alltables;
SELECT sum([number of tables]) "Total Number of Tables in all user databases" from #alltables;
drop table #alltables;
Select Count(*)
From INFORMATION_SCHEMA.TABLES
Where TABLE_TYPE = 'BASE TABLE'
If what you are seeking is a way to determine how many tables exist across all databases on a given SQL Server instance, then you need to cycle through each database. One way would be:
Declare #Databases Cursor
Declare #DbName as nvarchar(64)
Declare #SQL nvarchar(max)
Declare #BaseSQL nvarchar(max)
Declare #Count int
Declare #TotalCount int
Set #Databases = Cursor Fast_Forward For
select [name]
from master..sysdatabases
where [name] Not In('master','model','msdb','tempdb')
Open #Databases
Fetch Next From #Databases Into #DbName
Set #BaseSQL = 'Select #Count = Count(*)
From DatabaseName.INFORMATION_SCHEMA.TABLES
Where TABLE_TYPE = ''BASE TABLE'''
Set #TotalCount = 0
While ##Fetch_Status = 0
Begin
Set #Count = 0
Set #SQL = Replace(#BaseSQL, 'DatabaseName', QuoteName(#DbName))
exec sp_executesql #SQL, N'#Count int OUTPUT', #Count OUTPUT
Set #TotalCount = #TotalCount + #Count
Fetch Next From #Databases Into #DbName
End
Close #Databases
Deallocate #Databases
Select #TotalCount
This solution has the advantage of not using any undocumented features such as sp_MSforeachdb however it is obviously more verbose.
Related
I have created the following query which will get the data from all databases. when i execute the query i am getting error invalid column id. i have investigated and found the table tbl_table_A (example) is listed in master database and this table is not having column id. i have exlcluded this DB master but not sure why the query is still calling the master DB. kindly advise
Query :
CREATE TABLE ##tbl_data
(
[database_name] NVARCHAR(500),
id INT,
last_run DATETIME,
[next_run] DATETIME,
last_run_status NVARCHAR(500)
)
DECLARE #StartDate NVARCHAR(MAX)
DECLARE #EndDate NVARCHAR(MAX)
DECLARE #strSQL NVARCHAR(MAX)
SET #StartDate = '10-Dec-2019 00:12:59'
SET #EndDate = '10-Dec-2019 00:17:59'
SET #strSQL =
'
USE [?]
IF ''?'' <> ''master'' AND ''?'' <> ''model'' AND ''?'' <> ''msdb'' AND ''?'' <> ''tempdb''
BEGIN
IF OBJECT_ID(''tbl_table_A'') IS NULL
RETURN;
insert into ##tbl_data
SELECT ''?'', id,last_run,next_run,last_run_status
FROM dbo.tbl_table_A nolock
WHERE last_run between cast ('''+#StartDate+''' as Datetime2) and cast ('''+#EndDate+''' as Datetime2)
END'
EXEC dbo.sp_msforeachdb #strSQL
Select * from ##tbl_data
Drop table ##tbl_data
i have exlcluded this DB master but not sure why the query is still
calling the master DB
No, your code does not "call" master.
Here is your code where I use print instead of insert.
This way you can see what exactly db is checked and whether there is or there is not your table there:
declare #strSQL NVARCHAR(MAX)
SET #strSQL =
'
USE [?]
IF ''?'' <> ''master'' AND ''?'' <> ''model'' AND ''?'' <> ''msdb'' AND ''?'' <> ''tempdb''
BEGIN
print ''?''
IF OBJECT_ID(''tbl_table_A'') IS NULL
begin
print ''there is no table tbl_table_A''
print ''----------------''
RETURN;
end
print ''***** THERE IS table tbl_table_A *****''
print ''----------------''
END'
EXEC dbo.sp_msforeachdb #strSQL
I always like to take a different approach to these types of problems. For one, I really dislike cursors and you don't really need one here. Also, sp_msforeachdb is not only undocumented it has some problems. It will sometimes skip databases and nobody really seems to know why. Aaron Bertrand discusses this and provides a better alternative here. https://sqlblog.org/2010/12/29/a-more-reliable-and-more-flexible-sp_msforeachdb
I prefer to do something like below. There are no loops and won't run into weird behavior like skipping tables. It also does not require a global temp table which can have serious concurrency issues. This requires two dynamic sql statements. The first gets the list of databases with the table you want to find. Then we use that data to generate the dynamic sql statement against the list of database we want to search.
if OBJECT_ID('tempdb..#Databases') is not null
drop table #Databases
DECLARE #StartDate NVARCHAR(MAX)
, #EndDate NVARCHAR(MAX)
, #strSQL NVARCHAR(MAX)
SELECT #StartDate = '20191210 00:12:59'
, #EndDate = '20191210 00:17:59'
, #strSQL = ''
declare #TableName sysname = 'tbl_table_A'
select #strSQL = #strSQL + 'select ''' + d.name + ''' from ' + quotename(d.name) + '.sys.tables where name = ''' + #TableName + ''' union all '
from sys.databases d
select #strSQL = left(#strSQL, len(#strSql) - 10) --this removes the last union all
CREATE TABLE #Databases
(
DatabaseName sysname
)
--select #strSQL
insert #Databases
(
DatabaseName
)
exec sp_executesql #strSQL
set #strSQL = ''
select #strSQL = #strSQL + 'select ''' + d.DatabaseName + ''', id, last_run, next_run, last_run_status from ' + quotename(d.DatabaseName) + '.dbo.' + #TableName + ' where last_run between #_StartDate and #_EndDate union all '
from #Databases d
select #strSQL = left(#strSQL, len(#strSql) - 10)
--select #strSQL
exec sp_executesql #strSQL, N'#_StartDate datetime, #_EndDate datetime', #_StartDate = #StartDate, #_EndDate = #EndDate
I am trying to execute this query:
declare #tablename varchar(50)
set #tablename = 'test'
select * from #tablename
This produces the following error:
Msg 1087, Level 16, State 1, Line 5
Must declare the table variable "#tablename".
What's the right way to have the table name populated dynamically?
For static queries, like the one in your question, table names and column names need to be static.
For dynamic queries, you should generate the full SQL dynamically, and use sp_executesql to execute it.
Here is an example of a script used to compare data between the same tables of different databases:
Static query:
SELECT * FROM [DB_ONE].[dbo].[ACTY]
EXCEPT
SELECT * FROM [DB_TWO].[dbo].[ACTY]
Since I want to easily change the name of table and schema, I have created this dynamic query:
declare #schema sysname;
declare #table sysname;
declare #query nvarchar(max);
set #schema = 'dbo'
set #table = 'ACTY'
set #query = '
SELECT * FROM [DB_ONE].' + QUOTENAME(#schema) + '.' + QUOTENAME(#table) + '
EXCEPT
SELECT * FROM [DB_TWO].' + QUOTENAME(#schema) + '.' + QUOTENAME(#table);
EXEC sp_executesql #query
Since dynamic queries have many details that need to be considered and they are hard to maintain, I recommend that you read: The curse and blessings of dynamic SQL
Change your last statement to this:
EXEC('SELECT * FROM ' + #tablename)
This is how I do mine in a stored procedure. The first block will declare the variable, and set the table name based on the current year and month name, in this case TEST_2012OCTOBER. I then check if it exists in the database already, and remove if it does. Then the next block will use a SELECT INTO statement to create the table and populate it with records from another table with parameters.
--DECLARE TABLE NAME VARIABLE DYNAMICALLY
DECLARE #table_name varchar(max)
SET #table_name =
(SELECT 'TEST_'
+ DATENAME(YEAR,GETDATE())
+ UPPER(DATENAME(MONTH,GETDATE())) )
--DROP THE TABLE IF IT ALREADY EXISTS
IF EXISTS(SELECT name
FROM sysobjects
WHERE name = #table_name AND xtype = 'U')
BEGIN
EXEC('drop table ' + #table_name)
END
--CREATES TABLE FROM DYNAMIC VARIABLE AND INSERTS ROWS FROM ANOTHER TABLE
EXEC('SELECT * INTO ' + #table_name + ' FROM dbo.MASTER WHERE STATUS_CD = ''A''')
Use:
CREATE PROCEDURE [dbo].[GetByName]
#TableName NVARCHAR(100)
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
DECLARE #sSQL nvarchar(500);
SELECT #sSQL = N'SELECT * FROM' + QUOTENAME(#TableName);
EXEC sp_executesql #sSQL
END
You can't use a table name for a variable. You'd have to do this instead:
DECLARE #sqlCommand varchar(1000)
SET #sqlCommand = 'SELECT * from yourtable'
EXEC (#sqlCommand)
You'll need to generate the SQL content dynamically:
declare #tablename varchar(50)
set #tablename = 'test'
declare #sql varchar(500)
set #sql = 'select * from ' + #tablename
exec (#sql)
Use sp_executesql to execute any SQL, e.g.
DECLARE #tbl sysname,
#sql nvarchar(4000),
#params nvarchar(4000),
#count int
DECLARE tblcur CURSOR STATIC LOCAL FOR
SELECT object_name(id) FROM syscolumns WHERE name = 'LastUpdated'
ORDER BY 1
OPEN tblcur
WHILE 1 = 1
BEGIN
FETCH tblcur INTO #tbl
IF ##fetch_status <> 0
BREAK
SELECT #sql =
N' SELECT #cnt = COUNT(*) FROM dbo.' + quotename(#tbl) +
N' WHERE LastUpdated BETWEEN #fromdate AND ' +
N' coalesce(#todate, ''99991231'')'
SELECT #params = N'#fromdate datetime, ' +
N'#todate datetime = NULL, ' +
N'#cnt int OUTPUT'
EXEC sp_executesql #sql, #params, '20060101', #cnt = #count OUTPUT
PRINT #tbl + ': ' + convert(varchar(10), #count) + ' modified rows.'
END
DEALLOCATE tblcur
You need to use the SQL Server dynamic SQL:
DECLARE #table NVARCHAR(128),
#sql NVARCHAR(MAX);
SET #table = N'tableName';
SET #sql = N'SELECT * FROM ' + #table;
Use EXEC to execute any SQL:
EXEC (#sql)
Use EXEC sp_executesql to execute any SQL:
EXEC sp_executesql #sql;
Use EXECUTE sp_executesql to execute any SQL:
EXECUTE sp_executesql #sql
Declare #tablename varchar(50)
set #tablename = 'Your table Name'
EXEC('select * from ' + #tablename)
Also, you can use this...
DECLARE #SeqID varchar(150);
DECLARE #TableName varchar(150);
SET #TableName = (Select TableName from Table);
SET #SeqID = 'SELECT NEXT VALUE FOR ' + #TableName + '_Data'
exec (#SeqID)
Declare #fs_e int, #C_Tables CURSOR, #Table varchar(50)
SET #C_Tables = CURSOR FOR
select name from sysobjects where OBJECTPROPERTY(id, N'IsUserTable') = 1 AND name like 'TR_%'
OPEN #C_Tables
FETCH #C_Tables INTO #Table
SELECT #fs_e = sdec.fetch_Status FROM sys.dm_exec_cursors(0) as sdec where sdec.name = '#C_Tables'
WHILE ( #fs_e <> -1)
BEGIN
exec('Select * from ' + #Table)
FETCH #C_Tables INTO #Table
SELECT #fs_e = sdec.fetch_Status FROM sys.dm_exec_cursors(0) as sdec where sdec.name = '#C_Tables'
END
I am using SQL Server 2012.
The first part of my query is already answered in this thread. But I also want a second column that will show the corresponding maximum value of that column in its corresponding table.
I have tried this approach: use a function that takes in table name and column name as parameter and return the max value. But it is illegal to use dynamic SQL from a function. Moreover, i cannot seem to call a function from within a SELECT query.
I have also tried using stored procedure, but i cannot figure out how to call it and use it. Please suggest alternative ways to achieve this.
I am new to SQL Server.
Thanks
I think the easiest solution would be stored procedure. As far as I know:
Dynamic SQL can't be placed in functions
Dynamic SQL can't be place in OPENROWSET
I addition, if you write such procedure:
Beware of names containing spaces, qoutes (SQL injection possible)
MAX(column) on non-Indexed columns would require full scan (can be very slow)
Table and column names can be duplicated (placed in differend schemas)
Id duplicates and performance is not a problem, take a look at the following snippet:
CREATE PROC FindMaxColumnValues
#type sysname = '%',
#table sysname = '%'
AS
DECLARE #result TABLE (TableName sysname, ColumnName sysname, MaxValue NVARCHAR(MAX))
DECLARE #tab sysname
DECLARE #col sysname
DECLARE cur CURSOR FOR
SELECT TABLE_NAME TableName, COLUMN_NAME [Column Name]
FROM INFORMATION_SCHEMA.COLUMNS
WHERE DATA_TYPE LIKE #type and TABLE_NAME LIKE #table
OPEN cur
FETCH NEXT FROM cur INTO #tab, #col
WHILE ##FETCH_STATUS = 0
BEGIN
DECLARE #sql nvarchar(MAX) = 'SELECT '+QUOTENAME(#tab,'''')+' [TableName], '+QUOTENAME(#col, '''')+' [ColumnName], MAX('+QUOTENAME(#col)+') FROM '+QUOTENAME(#tab)
INSERT INTO #result EXEC(#sql)
FETCH NEXT FROM cur INTO #tab, #col
END
CLOSE cur
DEALLOCATE cur
SELECT * FROM #result
Samples:
--MAX of INT's
EXEC FindMaxColumnValues 'INT'
--MAX of INT's in tables matching 'TestTab%'
EXEC FindMaxColumnValues 'INT', 'TestTab%'
--MAX of ALL columns
EXEC FindMaxColumnValues
Results:
TableName ColumnName MaxValue
IdNameTest ID 2
TestTable ID 5
TestTable Number 3
TableName ColumnName MaxValue
TestTable ID 5
TestTable Number 3
TableName ColumnName MaxValue
UpdateHistory UpdateTime 2016-07-14 12:21:37.00
IdNameTest ID 2
IdNameTest Name T2
TestTable ID 5
TestTable Name F
TestTable Number 3
You can use the below SP and enhance it per your Need,
CRETE PROCEDURE Getmaxtablecolval
AS
BEGIN
CREATE TABLE #t
(
tablename VARCHAR(50),
columnname VARCHAR(50),
id INT,
counts INT
)
INSERT INTO #t
SELECT table_name [Table Name],
column_name [Column Name],
NULL,
NULL
FROM information_schema.columns
WHERE data_type = 'INT'
BEGIN TRAN
DECLARE #id INT
SET #id = 0
UPDATE #t
SET #id = id = #id + 1
COMMIT TRAN
DECLARE #RowCount INT
SET #RowCount = (SELECT Count(0)
FROM #t)
DECLARE #I INT
SET #I = 1
DECLARE #Counter INT
DECLARE #TName VARCHAR(50)
DECLARE #CName VARCHAR(50)
DECLARE #DynamicSQL AS VARCHAR(500)
WHILE ( #I <= #RowCount )
BEGIN
SELECT #TName = tablename
FROM #t
WHERE id = #I
SELECT #CName = columnname
FROM #t
WHERE id = #I
SET #DynamicSQL = 'Update #T Set Counts = '
+ '(Select ISNull(Max(' + #CName + '), 0) From '
+ #TName + ') Where Id = '
+ CONVERT(VARCHAR(10), #I)
--PRINT #DynamicSQL
EXEC (#DynamicSQL)
SET #I = #I + 1
END
SELECT *
FROM #t
END
go
Getmaxtablecolval
You can create a procedure out of this:
CREATE PROCEDURE GET_COLUMNS_WITH_MAX_VALUE
#COLUMN_TYPE NVARCHAR(50)
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
-- DUMMY VARIABLE TO COPY STRUCTURE TO TEMP
DECLARE #DUMMY TABLE
(
TABLE_NAME NVARCHAR(50),
COLUMN_NAME NVARCHAR(50),
MAX_VALUE NVARCHAR(MAX)
)
-- CREATE TEMP TABLE FOR DYNAMIC SQL
SELECT TOP 0 * INTO #TABLE FROM #DUMMY
INSERT INTO #TABLE
(TABLE_NAME, COLUMN_NAME)
SELECT TABLE_NAME, COLUMN_NAME
FROM information_schema.columns where data_type = #COLUMN_TYPE
DECLARE #TABLE_NAME VARCHAR(50) -- database name
DECLARE #COLUMN_NAME VARCHAR(256) -- path for backup files
DECLARE db_cursor CURSOR FOR
SELECT TABLE_NAME, COLUMN_NAME
FROM #TABLE
OPEN db_cursor
FETCH NEXT FROM db_cursor INTO #TABLE_NAME, #COLUMN_NAME
WHILE ##FETCH_STATUS = 0
BEGIN
DECLARE #SQL NVARCHAR(MAX) = 'UPDATE #TABLE SET MAX_VALUE = (SELECT MAX([' + #COLUMN_NAME + ']) FROM [' + #TABLE_NAME + ']) '
+ 'WHERE [COLUMN_NAME] = ''' + #COLUMN_NAME + ''' AND TABLE_NAME = ''' + #TABLE_NAME + '''';
PRINT #SQL
EXEC (#SQL)
FETCH NEXT FROM db_cursor INTO #TABLE_NAME, #COLUMN_NAME
END
CLOSE db_cursor
DEALLOCATE db_cursor
SELECT * FROM #TABLE
DROP TABLE #TABLE
END
GO
Usage:
EXEC GET_COLUMNS_WITH_MAX_VALUE 'INT'
Results:
TABLE1 ID 50
TABLE2 ID 100
TABLE3 CarID 20
TABLE4 StudentID 30
Is there a generic stored procedure to audit the table. I have actually made one but I don't think its efficient and the stored procedure is quite long. If someone knows a better way to do it then please help me out...!
This is my table trigger.
ALTER TRIGGER [dbo].[Trigger3]
ON [dbo].[UserInfo]
AFTER Update
AS
BEGIN
SET NOCOUNT ON;
DECLARE #TABLENAME VARCHAR(50)
DECLARE #var varbinary
SELECT * INTO #TEMPINSERTED FROM inserted
SELECT * INTO #TEMPDELETED FROM deleted
SET #var = COLUMNS_UPDATED()
EXEC TetsProc #TEMPINSERTED, #TEMPDELETED, ##PROCID, #var
DROP TABLE #TEMPINSERTED
DROP TABLE #TEMPDELETED
END
This is my stored procedure
ALTER PROCEDURE [dbo].[TetsProc]
( #insertTable varchar(max),
#deleteTable varchar(max),
#IDZ varchar(max),
#var1 varbinary
)
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
DECLARE #TABLE AS TABLE (COL_NAME NVARCHAR(MAX))
DECLARE #idTable INT
SELECT #idTable = T.id
FROM sysobjects P JOIN sysobjects T ON P.parent_obj = T.id
WHERE P.id = #IDZ
declare #q1 nvarchar(max),#q2 nvarchar(max)
set #q1 = 'select * from ' + #insertTable
set #q2 = 'select * from ' + #deleteTable
DECLARE #TABLENAME NVARCHAR(250)
SELECT #TABLENAME = OBJECT_NAME(parent_obj)
FROM sysobjects WHERE ID = #IDZ
----RETURN COLUMNS IF THEY ARE UPDATED----
SELECT #idTable = T.id
FROM sysobjects P JOIN sysobjects T ON P.parent_obj = T.id
WHERE P.id = ##procid
DECLARE #Columns_UpdateD VARCHAR(50)
SELECT #Columns_Update = ISNULL(#Columns_Updated + ', ', '') + name
FROM syscolumns
WHERE id = #idTable
AND CONVERT(VARBINARY,REVERSE(#var1)) & POWER(CONVERT(BIGINT, 2), colorder - 1) > 0
select status into #TmpcolumnsUpdated from dbo.ParseByComma(#Columns_UpdateD)
DECLARE #QRY1 NVARCHAR(MAX)
DECLARE #QRY2 NVARCHAR(MAX)
declare #column_name varchar(50)
DECLARE cursorColumnName CURSOR FOR
select status from #TmpcolumnsUpdated
OPEN cursorColumnName
FETCH NEXT FROM cursorColumnName INTO #column_name
WHILE ##FETCH_STATUS = 0
BEGIN
SET #QRY1= 'SELECT '+#column_name + ' FROM '+ #insertTable
SET #QRY2= 'SELECT '+#column_name + ' FROM ' + #deleteTable
DECLARE #tab AS TABLE (OLD_COL VARCHAR(10))
DECLARE #tab1 AS TABLE (NEW_COL VARCHAR(10))
INSERT into #tab EXECUTE sp_executesql #QRY2
INSERT into #tab1 EXECUTE sp_executesql #QRY1
DECLARE #OLD_VALUE VARCHAR(MAX)=(SELECT OLD_COL FROM #tab)
DECLARE #NEW_VALUE VARCHAR(MAX)=(SELECT NEW_COL FROM #tab1)
IF(#OLD_VALUE!=#NEW_VALUE)
BEGIN
INSERT INTO UpdateInfo (Table_Name,Col_Name,Old_Value,New_Value,Time)
(
SELECT
#TABLENAME,
#column_name,
#OLD_VALUE,
#NEW_VALUE,
GETDATE()
)
SELECT * FROM UpdateInfo
END
DELETE FROM #tab
DELETE FROM #tab1
FETCH NEXT FROM cursorColumnName INTO #column_name
END
CLOSE cursorColumnName
DEALLOCATE cursorColumnName
drop table #TmpcolumnsUpdated
END
Looks like a sure way to drag down the performance of your server.
If you are using SQL Server 2012, I'd recommend you to check out Sql Server Audit instead.
If you have to stick with your mechanism, at the very least lose the cursor in the PROC.
We have a database setup that consists of two parts: a static structure, and dynamic additions. For each database, the dynamic can be different, and sometimes we don't have data for all the dynamic fields. Rigt now, we check for empties by looking at the total count of records in the entire table, but we want to move to a more refined method of checking for empties if possible. Is it possible to quickly check through several hundred fields and see which ones are empty and which ones are populated?
For searching for any rows that have NULLS in any column you can do this, first create this proc which is based on the code here Search all columns in all the tables in a database for a specific value
CREATE PROCEDURE FindMyData_StringNull
#DataToFind NVARCHAR(4000),
#ExactMatch BIT = 0
AS
SET NOCOUNT ON
DECLARE #Temp TABLE(RowId INT IDENTITY(1,1), SchemaName sysname, TableName sysname, ColumnName SysName, DataType VARCHAR(100), DataFound BIT)
INSERT INTO #Temp(TableName,SchemaName, ColumnName, DataType)
SELECT C.Table_Name,C.TABLE_SCHEMA, C.Column_Name, C.Data_Type
FROM Information_Schema.Columns AS C
INNER Join Information_Schema.Tables AS T
ON C.Table_Name = T.Table_Name
AND C.TABLE_SCHEMA = T.TABLE_SCHEMA
WHERE Table_Type = 'Base Table'
DECLARE #i INT
DECLARE #MAX INT
DECLARE #TableName sysname
DECLARE #ColumnName sysname
DECLARE #SchemaName sysname
DECLARE #SQL NVARCHAR(4000)
DECLARE #PARAMETERS NVARCHAR(4000)
DECLARE #DataExists BIT
DECLARE #SQLTemplate NVARCHAR(4000)
SELECT #SQLTemplate = 'If Exists(Select *
From ReplaceTableName
Where Convert(nVarChar(4000), [ReplaceColumnName])
IS NULL
)
Set #DataExists = 1
Else
Set #DataExists = 0'
,
#PARAMETERS = '#DataExists Bit OUTPUT',
#i = 1
SELECT #i = 1, #MAX = MAX(RowId)
FROM #Temp
WHILE #i <= #MAX
BEGIN
SELECT #SQL = REPLACE(REPLACE(#SQLTemplate, 'ReplaceTableName', QUOTENAME(SchemaName) + '.' + QUOTENAME(TableName)), 'ReplaceColumnName', ColumnName)
FROM #Temp
WHERE RowId = #i
PRINT #SQL
EXEC SP_EXECUTESQL #SQL, #PARAMETERS, #DataExists = #DataExists OUTPUT
IF #DataExists =1
UPDATE #Temp SET DataFound = 1 WHERE RowId = #i
SET #i = #i + 1
END
SELECT SchemaName,TableName, ColumnName
FROM #Temp
WHERE DataFound = 1
Call it like this
FindMyData_StringNull NULL,1
Assuming that you are just checking for whether or not there are any non-NULL values in the column, using EXISTS should generally be faster than getting a COUNT(*). The COUNT needs to scan the whole table to come up with the correct number. EXISTS just needs to find one row that satisfies the condition before it stops looking.
If the whole column is NULL then the time will be about the same, but in all of those cases where you have values it could be substantially shorter.
From Search all columns in all the tables in a database for a specific value
first create this function
CREATE PROCEDURE FindMyData_String
#DataToFind NVARCHAR(4000),
#ExactMatch BIT = 0
AS
SET NOCOUNT ON
DECLARE #Temp TABLE(RowId INT IDENTITY(1,1), SchemaName sysname, TableName sysname, ColumnName SysName, DataType VARCHAR(100), DataFound BIT)
INSERT INTO #Temp(TableName,SchemaName, ColumnName, DataType)
SELECT C.Table_Name,C.TABLE_SCHEMA, C.Column_Name, C.Data_Type
FROM Information_Schema.Columns AS C
INNER Join Information_Schema.Tables AS T
ON C.Table_Name = T.Table_Name
AND C.TABLE_SCHEMA = T.TABLE_SCHEMA
WHERE Table_Type = 'Base Table'
And Data_Type In ('ntext','text','nvarchar','nchar','varchar','char')
DECLARE #i INT
DECLARE #MAX INT
DECLARE #TableName sysname
DECLARE #ColumnName sysname
DECLARE #SchemaName sysname
DECLARE #SQL NVARCHAR(4000)
DECLARE #PARAMETERS NVARCHAR(4000)
DECLARE #DataExists BIT
DECLARE #SQLTemplate NVARCHAR(4000)
SELECT #SQLTemplate = CASE WHEN #ExactMatch = 1
THEN 'If Exists(Select *
From ReplaceTableName
Where Convert(nVarChar(4000), [ReplaceColumnName])
= ''' + #DataToFind + '''
)
Set #DataExists = 1
Else
Set #DataExists = 0'
ELSE 'If Exists(Select *
From ReplaceTableName
Where Convert(nVarChar(4000), [ReplaceColumnName])
Like ''%' + #DataToFind + '%''
)
Set #DataExists = 1
Else
Set #DataExists = 0'
END,
#PARAMETERS = '#DataExists Bit OUTPUT',
#i = 1
SELECT #i = 1, #MAX = MAX(RowId)
FROM #Temp
WHILE #i <= #MAX
BEGIN
SELECT #SQL = REPLACE(REPLACE(#SQLTemplate, 'ReplaceTableName', QUOTENAME(SchemaName) + '.' + QUOTENAME(TableName)), 'ReplaceColumnName', ColumnName)
FROM #Temp
WHERE RowId = #i
PRINT #SQL
EXEC SP_EXECUTESQL #SQL, #PARAMETERS, #DataExists = #DataExists OUTPUT
IF #DataExists =1
UPDATE #Temp SET DataFound = 1 WHERE RowId = #i
SET #i = #i + 1
END
SELECT SchemaName,TableName, ColumnName
FROM #Temp
WHERE DataFound = 1
Now call it like this for rows with empty strings in any string type columns
exec FindMyData_String '',1
it will give you an output with column name, table name and schema name
Just keep in mind that it will search all tables
I would think the simplest solution is to use the CHECKSUM function. First you would want to determine the checksum on an empty row and then compare that to the other rows.
Select Checksum(*)
From Table
The catch with using * here is that it will include the PK. You would likely have to specify the individual columns excluding the PK to get an accurate read. So something like:
Select Checksum(Col1, Col2, Col3)
From Table
Checksum Function.