I have to check for value existence in a subset of tables in a subset of databases of a sql server instance. Beware I need to do this because I have 30 databases with same schema name and similar structure. Querying all databases separately is a waste of time.
The query generates correctly code for existing tables, but the additional check for column existence in table fails.
The column in some tables does not exist so the generated code must not include queries on tables without this column.
To solve this I need to realiably find a way to join sys.databases with sys.tables and then sys.columns. Or an alternative way to query all the required databases in a time saving manner.
SET NOCOUNT ON;
IF OBJECT_ID (N'tempdb.dbo.#temp') IS NOT NULL
DROP TABLE #temp
CREATE TABLE #temp
(
exist INT
, DB VARCHAR(50)
, tbname VARCHAR(500)
)
/*tables common root,
all tables i need to query start with this prefix and a number between 1 and 50
and some resulting tables do not exist
ex: dbo.Z_WBL_ASCHEDA23 exist in wbcto, while dbo.Z_WBL_ASCHEDA23 does not exist in db wbgtg
*/
DECLARE #TableName NVARCHAR(200)
SELECT #TableName = 'dbo.Z_WBL_ASCHEDA'
DECLARE #SQL NVARCHAR(MAX)
;WITH n(n) AS
(
SELECT 1
UNION ALL
SELECT n+1 FROM n WHERE n < 50
)
SELECT #SQL = STUFF((
SELECT CHAR(13)+'SELECT COUNT(1), ''' + db.name + ''', '''+
#TableName+CONVERT(VARCHAR, n.n)+''' FROM ' +#TableName+CONVERT(VARCHAR, n.n)
+ ' WHERE COALESCE(s_dettagli,'''') = ''CONTROLLATO'' '
+CHAR(13)
FROM sys.databases db
INNER JOIN n ON 1=1
INNER JOIN sys.tables t ON OBJECT_ID(db.name + '.' + #TableName+CONVERT(VARCHAR, n.n)) IS NOT NULL
INNER JOIN sys.columns c ON t.OBJECT_ID = c.OBJECT_ID and c.name = 's_dettagli'
/*join on columns not working, generates sql for tables without 's_dettagli' column and query fails*/
WHERE db.name like 'wb%' --check only databases starting with 'wb'
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 1, '')
select #SQL
INSERT INTO #temp (exist, DB, tbname)
EXEC sys.sp_executesql #SQL
SELECT *
FROM #temp t
where exist <> 0
EDIT: adding some sql generated from query
SELECT COUNT(1), 'wb360', 'dbo.Z_WBL_ASCHEDA23' FROM wb360.dbo.Z_WBL_ASCHEDA23 WHERE COALESCE(s_dettagli,'') = 'CONTROLLATO'
SELECT COUNT(1), 'Wbbim', 'dbo.Z_WBL_ASCHEDA32' FROM Wbbim.dbo.Z_WBL_ASCHEDA32 WHERE COALESCE(s_dettagli,'') = 'CONTROLLATO'
the table of first query doesn't contain 's_dettagli' column
EDIT2: SOLUTION
EXEC sp_MSforeachdb '
IF ''?'' not like ''wb%''
RETURN
USE [?]
EXEC sp_MSforeachtable
#replacechar = ''!'',
#command1 = ''SELECT ''''?'''' AS db_name, ''''!'''' AS table_name, COUNT(*) FROM ! '',
#whereand = '' And Object_id In (
Select t.Object_id
From sys.objects t
INNER JOIN sys.columns c on c.Object_id = t.Object_id
Where t.name like ''''Z_WBL_ASCHEDA%''''
AND c.name = ''''s_dettagli'''' )'' '
Sys.columns can be joined to sys.tables using the object_id field (the object_id is the representation of the table itself).
sys.tables is run in the context of the database you are querying, hence you cannot see a table contained in another database. sys.databases can be run on any database on an instance and allow you to view other databases on the same instance. As such you don't need to join the table to the database (also the reason why there is no database_id field within sys.tables).
I hope that helps. Any clarification please let me know.
I would suggest alternative ways:
use registered Servers in SSMS and run the script on each database here
use exec sys.sp_MSforeachdb here
use sqlcmd and powershell to switch databases
I believe this script can help you :
SET NOCOUNT ON;
IF OBJECT_ID (N'tempdb.dbo.#Temp') IS NOT NULL
DROP TABLE #Temp
CREATE TABLE #Temp
(
exist INT
, DB VARCHAR(50)
, tbname VARCHAR(500)
)
DECLARE #SchemaName NVARCHAR(200)
DECLARE #TableName NVARCHAR(200)
DECLARE #ColumnName NVARCHAR(200)
DECLARE #SearchText NVARCHAR(200)
DECLARE #DBNameStartWith NVARCHAR(200)
DECLARE #SQL NVARCHAR(MAX)
SET #DBNameStartWith = 'wb'
SET #SchemaName = 'dbo'
SET #TableName = 'Z_WBL_ASCHEDA'
SET #ColumnName = 's_dettagli'
SET #SearchText = 'CONTROLLATO'
DECLARE #DatabaseName varchar(100)
DECLARE Crsr CURSOR FOR
SELECT name
FROM MASTER.sys.sysdatabases
WHERE name LIKE ''+#DBNameStartWith+'%'
OPEN Crsr
FETCH NEXT FROM Crsr INTO #DatabaseName
WHILE ##FETCH_STATUS = 0
BEGIN
IF ISNULL((SELECT COUNT(1) FROM SYS.TABLES T,SYS.COLUMNS C WHERE T.object_id=C.object_id AND T.name=#TableName AND C.name=#ColumnName),0)>0
BEGIN
SET #SQL = '
IF EXISTS (SELECT 1 FROM '+#DatabaseName+'.SYS.TABLES T,'+#DatabaseName+'.SYS.COLUMNS C WHERE T.object_id=C.object_id AND T.name='''+#TableName+''' AND C.name='''+#ColumnName+''')
BEGIN
SELECT COUNT(1),'''+#DatabaseName+''','''+#TableName+'''
FROM '+#DatabaseName+'.'+#SchemaName+'.'+#TableName+'
WHERE '+#ColumnName+'=''' +#SearchText+'''
END'
PRINT(#SQL)
INSERT INTO #Temp
EXEC sp_executesql #SQL
END
FETCH NEXT FROM Crsr INTO #DatabaseName
END
CLOSE Crsr
DEALLOCATE Crsr
SELECT * FROM #Temp
Does anyone know how to check a a variable against all database table with columns storing the same type of information? I have a poorly designed database that stores ssn in over 60 tables within one database. some of the variations of columns in the various tables include:
app_ssn
ca_ssn
cand_ssn
crl_ssn
cu_ssn
emtaddr_ssn
re_ssn
sfcart_ssn
sfordr_ssn
socsecno
ssn
Ssn
SSN
I want to create a stored procedure that will accept a value and check it against every table that has 'ssn' in the name.Does anyone have idea as to how to do this?
-- I assume that table/column names don't need to be surrounded by square braces. You may want to save matches in a table - I just select them. I also assume ssn is a char.
alter proc proc1
#search1 varchar(500)
as
begin
set nocount on
declare #strsql varchar(500)
declare #curtable sysname
declare #prevtable sysname
declare #column sysname
select top 1 #curtable= table_schema+'.'+table_name, #column=column_name
from INFORMATION_SCHEMA.COLUMNS
where CHARINDEX('ssn',column_name) > 0
order by table_schema+'.'+table_name +column_name
-- make sure that at least one column has ssn in the column name
if #curtable is not null
begin
while (1=1)
begin
set #strsql = 'select * from ' +#curtable +' where '+''''+#search1+''''+ ' = '+#column
print #strsql
-- any matches for passed in ssn will match here...
exec (#strsql)
set #prevtable = #curtable+#column
select top 1 #curtable= table_schema+'.'+table_name, #column=column_name
from INFORMATION_SCHEMA.COLUMNS
where CHARINDEX('ssn',column_name) > 0
and table_schema+'.'+table_name +column_name> #prevtable
order by table_schema+'.'+table_name +column_name
-- when we run out of columns that contain ssn we are done...
if ##ROWCOUNT = 0
break
end
end
end
What you will need to do is some research. But here is where you can start;
SELECT tbl.NAME AS TableName
,cl.NAME AS ColumnName
,IDENTITY(INT, 1, 1) AS ID
INTO #ColumnsToLoop
FROM sys.tables tbl
JOIN sys.columns cl ON cl.object_id = tbl.object_id
This will give you the table / column relation then you can simply build a dynamic SQL string based on each row in the query above (basically loop it) and use EXEC or sp_execsql. So basically;
DECLARE #Loop int = (select min(ID) From #ColumnsToLoop),#MX int = (Select MAX(ID) From #ColumnsToLoop)
WHILE(#Loop<=#MX)
BEGIN
DECLARE #SQL nvarchar(MAX) = 'SQL String'
//Construct the dynamic SQL String
EXEC(#SQL);
SET #Loop += 1
END
Perhaps I went a little too crazy with this one, but let me know. I thought it would best the primary key of the search results with the table name so you could join it to your tables. I also managed to do it without a single cursor or loop.
DECLARE #SSN VARCHAR(25) = '%99%',
#SQL VARCHAR(MAX);
WITH CTE_PrimaryKeys
AS
(
SELECT TABLE_CATALOG,
TABLE_SCHEMA,
TABLE_NAME,
column_name
FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE D
WHERE OBJECTPROPERTY(OBJECT_ID(constraint_name), 'IsPrimaryKey') = 1
),
CTE_Columns
AS
(
SELECT A.*,
CONCAT(A.TABLE_CATALOG,'.',A.TABLE_SCHEMA,'.',A.TABLE_NAME) AS FullTableName,
CASE WHEN B.COLUMN_NAME IS NOT NULL THEN 1 ELSE 0 END AS IsPrimaryKey
FROM INFORMATION_SCHEMA.COLUMNS A
LEFT JOIN CTE_PrimaryKeys B
ON A.TABLE_CATALOG = B.TABLE_CATALOG
AND A.TABLE_SCHEMA = B.TABLE_SCHEMA
AND A.TABLE_NAME = B.TABLE_NAME
AND A.COLUMN_NAME = B.COLUMN_NAME
),
CTE_Select
AS
(
SELECT
'SELECT ' +
--This returns the pk_col casted as Varchar and the table name in another columns
STUFF((SELECT ',CAST(' + COLUMN_NAME + ' AS VARCHAR(MAX)) AS pk_col,''' + B.TABLE_NAME + ''' AS Table_Name'
FROM CTE_Columns B
WHERE A.Table_Name = B.TABLE_NAME
AND B.IsPrimaryKey = 1
FOR XML PATH ('')),1,1,'')
+ ' FROM ' + fullTableName +
--This is where I list the columns where LIKE desired SSN
' WHERE ' +
STUFF((SELECT COLUMN_NAME + ' LIKE ''' + #SSN + ''' OR '
FROM CTE_Columns B
WHERE A.Table_Name = B.TABLE_NAME
--This is where I filter so I only get desired columns
AND (
--Uncomment the Collate if your database is case sensitive
COLUMN_NAME /*COLLATE SQL_Latin1_General_CP1_CI_AS*/ LIKE '%ssn%'
--list your column Names that don't have ssn in them
--OR COLUMN_NAME IN ('col1','col2')
)
FOR XML PATH ('')),1,0,'') AS Selects
FROM CTE_Columns A
GROUP BY A.FullTableName,A.TABLE_NAME
)
--Unioning them all together and getting rid of last trailing "OR "
SELECT #SQL = COALESCE(#sql,'') + SUBSTRING(selects,1,LEN(selects) - 3) + ' UNION ALL ' + CHAR(13) --new line for easier debugging
FROM CTE_Select
WHERE selects IS NOT NULL
--Look at your code
SELECT SUBSTRING(#sql,1,LEN(#sql) - 11)
We're going to be going through a period of testing on a product soon. This product is a web application with a SQL Server 2008R2 backend.
Our database has several schemas within it (Customer, DataEntry, and a few others).
I have found ways to wipe all data in a database without breaking referential integrity or the data structures, which is close to what we're looking to do. The problem I'm finding is that we actually need a bunch of the data from some of the tables. Essentially, we only want to wipe the Customers schema.
We have a script written which will load in the test data for customers, but is there a way to change the techniques in my linked article to target only a specific schema? Is there a better way to clear all data in a schema?
A common scenario for me as well. I usually write what I call a reset script, deleting all data form the target tables in the order necessary to prevent referential errors, and then reseed the primary keys.
DELETE FROM < table 1 >
DELETE FROM < table 2 >
... etc ...
DBCC CHECKIDENT (< table 1 >, RESEED, 0)
DBCC CHECKIDENT (< table 2 >, RESEED, 0)
... etc ...
EDIT
To more fully answer the original question. to leave data in specific tables you would need to modify the block of code that does the deleting / truncating, and also modify the code that reseeds the idents in a similar way.
EXEC sp_MSForEachTable '
IF object_id(''?'') != < table name > AND object_id(''?'') != < table name > AND ... etc ...
BEGIN
IF OBJECTPROPERTY(object_id(''?''), ''TableHasForeignRef'') = 1
DELETE FROM ?
ELSE
TRUNCATE TABLE ?
END
'
GO
Just set the #schemaID to the name of the schema you wish to blow away and it should do the rest. If you end up with a FK dependency loop it will break and tell you what to do...
Declare #schemaID Nvarchar(256)
Set #schemaID = 'Schema' -- Set this to the name of the schema you wish to blow away
If Object_ID('tempdb..#tables') Is Not Null Drop Table #tables
Create Table #tables (tID Int, SchemaName Nvarchar(256), TableName Nvarchar(256))
Insert #tables
Select Row_Number() Over (Order By s.name, so.name), s.name, so.name
From sysobjects so
Join sys.schemas s
On so.uid = s.schema_id
Where so.xtype = 'u'
And s.name = #schemaID
Declare #SQL Nvarchar(Max),
#schema Nvarchar(256),
#table Nvarchar(256),
#iter Int = 1,
#loopCatch Int = 0
While Exists (Select 1
From #tables)
Begin
Select #schema = SchemaName,
#table = TableName
From #tables
Where tID = #iter
If Exists (Select 1
From sysobjects o
Join sys.schemas s1
On o.uid = s1.schema_id
Join sysforeignkeys fk
On o.id = fk.rkeyid
Join sysobjects o2
On fk.fkeyid = o2.id
Join sys.schemas s2
On o2.uid = s2.schema_id
Join #tables t
On o2.name = t.TableName Collate Database_Default
And s2.name = t.SchemaName Collate Database_Default
Where o.name = #table
And s1.name = #schema)
Begin
Update t
Set tID = (Select Max(tID) From #tables) + 1
From #tables t
Where tableName = #table
And schemaName = #schema
Set #iter = #iter + 1
End
Else
Begin
Set #Sql = 'Truncate Table [' + #schema + '].[' + #table + ']'
Begin Try
Exec sp_executeSQL #SQL;
Delete t
From #tables t
Where tableName = #table
And schemaName = #schema
Set #iter = #iter + 1
End Try
Begin Catch
Print #SQL
Update t
Set tID = (Select Max(tID) From #tables) + 1
From #tables t
Where tableName = #table
And schemaName = #schema
Set #iter = #iter + 1
Set #loopCatch = #loopCatch + 1;
If #loopCatch > 5
Begin
Select 'WARNING: Endless FK redundancy loop. Drop the constraints and these tables, truncate and reapply constraints manually'
Union All
Select '[' + SchemaName + '].[' + TableName + ']'
From #tables;
Break;
End
End Catch
End
End
This is parameterized on database and schema. If no schema is supplied, it will clear all data in the specified database.
Handles tables with foreign key references appropriately by disabling constraints. If the procedure fails, which it shouldn't normally do, ensure that you run it successfully after fixing the cause of the problem, which should ensure constraint checking goes back to normal.
This will not handle foreign key references correctly if you have foreign keys between schemas, however, it could be fairly easily amended to handle this.
create procedure [removeData] (#database_name sysname, #schema_name sysname = null)
as
set nocount on
create table #tables (
TableName varchar(900) not null primary key,
HasFKRef bit not null
);
declare #sql nvarchar(4000),
#table_name varchar(900);
if (db_id(#database_name) is null)
raiserror ('You must at least specify the database name', 16, 1);
set #sql = 'select ''['' + TABLE_CATALOG + ''].['' + TABLE_SCHEMA + ''].['' + TABLE_NAME + '']'' as TableName, (case when exists(select * from [' + #database_name + '].INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc inner join [' + #database_name + '].INFORMATION_SCHEMA.TABLE_CONSTRAINTS tc on rc.UNIQUE_CONSTRAINT_CATALOG = tc.CONSTRAINT_CATALOG and rc.UNIQUE_CONSTRAINT_SCHEMA = tc.CONSTRAINT_SCHEMA and rc.UNIQUE_CONSTRAINT_NAME = tc.CONSTRAINT_NAME where tc.TABLE_NAME = t.TABLE_NAME) then 1 else 0 end) as HasFKRef
from [' + #database_name + '].INFORMATION_SCHEMA.TABLES t
where TABLE_TYPE = ''BASE TABLE'' and TABLE_SCHEMA = isnull(#schema_name, TABLE_SCHEMA)';
insert into #tables
exec sp_executesql #sql, N'#schema_name sysname', #schema_name;
declare #curse cursor
set #curse = cursor fast_forward for
select sql from (
select 'alter table ' + TableName + ' nocheck constraint all' as sql, 1 as sort
from #tables
union all
select 'truncate table ' + TableName, 2 as sort
from #tables
where HasFKRef = 0
union all
select 'delete from ' + TableName, 3 as sort
from #tables
where HasFKRef = 1
union all
select 'alter table ' + TableName + ' with check check constraint all', 4 as sort
from #tables
) t
order by sort, sql
open #curse
fetch next from #curse into #sql
while (##fetch_status = 0)
begin
exec (#sql)
fetch next from #curse into #sql
end
close #curse
GO
I am using SQL Server. I want to add a single column named [DateCreated] to multiple tables. Is it possible that with a single statement I could add this column to all the tables in my database?
I stumble upon an answer by Joe Steffaneli in which he suggested a query which in turn returns rows consisting Alter table statements.
Query is as follows :
select 'alter table ' + quotename(s.name) + '.' + quotename(t.name) + ' add [DateModified] datetime'
from sys.columns c
inner join sys.tables t
on c.object_id = t.object_id
inner join sys.schemas s
on t.schema_id = s.schema_id
left join sys.columns c2
on t.object_id = c2.object_id
and c2.name = 'DateModified'
where c.name = 'DateCreated'
and t.type = 'U'
and c2.column_id is null /* DateModified column does not already exist */
Is there any way that I can execute returned rows? Sorry for English.
You probably need something like this. Check that the script does what you want before running it (adds a non null column with a default value of getdate())!
DECLARE #Dynsql nvarchar(max)
SET #Dynsql = ''
SELECT #Dynsql = #Dynsql + '
alter table ' + QUOTENAME(SCHEMA_NAME(schema_id))+ '.' + QUOTENAME(name) +
' add [DateCreated] datetime not null default getdate()'
FROM sys.tables
WHERE type='U' and object_id NOT IN (select object_id from sys.columns where name='DateCreated')
EXEC (#Dynsql)
You can use this query
I use the where clause in this query (it is optional) to find all tables that have ID and add the new field to them.
you can change where clause for example find all tables that have BusinessId column and add new filed or remove where clause and add for all tables
DECLARE #SQL varchar(max)
SELECT #SQL= STUFF((SELECT ';' + 'ALTER TABLE ' + t.TABLE_SCHEMA+'.' +t.TABLE_NAME+ ' ADD newfield nvarchar(max)'
from information_schema.tables t
inner join information_schema.columns c on c.table_name = t.table_name
and c.table_schema = t.table_schema
where c.column_name = 'id'
and t.table_schema not in ('information_schema', 'pg_catalog')
and t.table_type = 'BASE TABLE'
FOR XML PATH('')),1,1,'')
EXEC (#SQL)
This stored procedure works fine
USE databaseName;
exec sp_msforeachtable 'alter table ? Add [DateCreated] datetime not null default getdate()';
declare #i int
set #i=1
while(#i<45)
begin
declare #sql varchar(200)
with TempTable as (select Row_number() over(order by stdID) as RowNo,* from SomeTable)
select #sql= 'alter table Table'+(select Name from TempTable where RowNo=#i)+' add NewColumn int'
exec (#sql)
set #i=#i+1
end
No, there is no single statement that will add a column to all the tables in your database.
Next time please tag your question with the RDBMS you're using. If there were a way, we wouldn't be able to give you the command without knowing which database system you are using.
I have a database full of customer data. It's so big that it's really cumbersome to operate on, and I'd rather just slim it down to 10% of the customers, which is plenty for development. I have an awful lot of tables and I don't want to alter them all with "ON DELETE CASCADE", especially because this is a one-time deal.
Can I do a delete operation that cascades through all my tables without setting them up first? If not, what is my best option?
Combining your advice and a script I found online, I made a procedure that will produce SQL you can run to perform a cascaded delete regardless of ON DELETE CASCADE. It was probably a big waste of time, but I had a good time writing it. An advantage of doing it this way is, you can put a GO statement between each line, and it doesn't have to be one big transaction. The original was a recursive procedure; this one unrolls the recursion into a stack table.
create procedure usp_delete_cascade (
#base_table_name varchar(200), #base_criteria nvarchar(1000)
)
as begin
-- Adapted from http://www.sqlteam.com/article/performing-a-cascade-delete-in-sql-server-7
-- Expects the name of a table, and a conditional for selecting rows
-- within that table that you want deleted.
-- Produces SQL that, when run, deletes all table rows referencing the ones
-- you initially selected, cascading into any number of tables,
-- without the need for "ON DELETE CASCADE".
-- Does not appear to work with self-referencing tables, but it will
-- delete everything beneath them.
-- To make it easy on the server, put a "GO" statement between each line.
declare #to_delete table (
id int identity(1, 1) primary key not null,
criteria nvarchar(1000) not null,
table_name varchar(200) not null,
processed bit not null,
delete_sql varchar(1000)
)
insert into #to_delete (criteria, table_name, processed) values (#base_criteria, #base_table_name, 0)
declare #id int, #criteria nvarchar(1000), #table_name varchar(200)
while exists(select 1 from #to_delete where processed = 0) begin
select top 1 #id = id, #criteria = criteria, #table_name = table_name from #to_delete where processed = 0 order by id desc
insert into #to_delete (criteria, table_name, processed)
select referencing_column.name + ' in (select [' + referenced_column.name + '] from [' + #table_name +'] where ' + #criteria + ')',
referencing_table.name,
0
from sys.foreign_key_columns fk
inner join sys.columns referencing_column on fk.parent_object_id = referencing_column.object_id
and fk.parent_column_id = referencing_column.column_id
inner join sys.columns referenced_column on fk.referenced_object_id = referenced_column.object_id
and fk.referenced_column_id = referenced_column.column_id
inner join sys.objects referencing_table on fk.parent_object_id = referencing_table.object_id
inner join sys.objects referenced_table on fk.referenced_object_id = referenced_table.object_id
inner join sys.objects constraint_object on fk.constraint_object_id = constraint_object.object_id
where referenced_table.name = #table_name
and referencing_table.name != referenced_table.name
update #to_delete set
processed = 1
where id = #id
end
select 'print ''deleting from ' + table_name + '...''; delete from [' + table_name + '] where ' + criteria from #to_delete order by id desc
end
exec usp_delete_cascade 'root_table_name', 'id = 123'
Here's a version of the accepted answer optimised for sparsely populated data models. It checks for the existence of data in a FK chain before adding it to the deletion list. I use it to clean up test data.
Don't use it in an active transactional db- it will hold locks way too long.
/*
-- ============================================================================
-- Purpose: Performs a cascading hard-delete.
-- Not for use on an active transactional database- it holds locks for too long.
-- (http://stackoverflow.com/questions/116968/in-sql-server-2005-can-i-do-a-cascade-delete-without-setting-the-property-on-my)
-- eg:
exec dbo.hp_Common_Delete 'tblConsumer', 'Surname = ''TestDxOverdueOneReviewWm''', 1
-- ============================================================================
*/
create proc [dbo].[hp_Common_Delete]
(
#TableName sysname,
#Where nvarchar(4000), -- Shouldn't include 'where' keyword, e.g. Surname = 'smith', NOT where Surname = 'smith'
#IsDebug bit = 0
)
as
set nocount on
begin try
-- Prepare tables to store deletion criteria.
-- #tmp_to_delete stores criteria that is tested for results before being added to #to_delete
create table #to_delete
(
id int identity(1, 1) primary key not null,
criteria nvarchar(4000) not null,
table_name sysname not null,
processed bit not null default(0)
)
create table #tmp_to_delete
(
id int primary key identity(1,1),
criteria nvarchar(4000) not null,
table_name sysname not null
)
-- Open a transaction (it'll be a long one- don't use this on production!)
-- We need a transaction around criteria generation because we only
-- retain criteria that has rows in the db, and we don't want that to change under us.
begin tran
-- If the top-level table meets the deletion criteria, add it
declare #Sql nvarchar(4000)
set #Sql = 'if exists(select top(1) * from ' + #TableName + ' where ' + #Where + ')
insert #to_delete (criteria, table_name) values (''' + replace(#Where, '''', '''''') + ''', ''' + #TableName + ''')'
exec (#Sql)
-- Loop over deletion table, walking foreign keys to generate delete targets
declare #id int, #tmp_id int, #criteria nvarchar(4000), #new_criteria nvarchar(4000), #table_name sysname, #new_table_name sysname
while exists(select 1 from #to_delete where processed = 0)
begin
-- Grab table/criteria to work on
select top(1) #id = id,
#criteria = criteria,
#table_name = table_name
from #to_delete
where processed = 0
order by id desc
-- Insert all immediate child tables into a temp table for processing
insert #tmp_to_delete
select referencing_column.name + ' in (select [' + referenced_column.name + '] from [' + #table_name +'] where ' + #criteria + ')',
referencing_table.name
from sys.foreign_key_columns fk
inner join sys.columns referencing_column on fk.parent_object_id = referencing_column.object_id
and fk.parent_column_id = referencing_column.column_id
inner join sys.columns referenced_column on fk.referenced_object_id = referenced_column.object_id
and fk.referenced_column_id = referenced_column.column_id
inner join sys.objects referencing_table on fk.parent_object_id = referencing_table.object_id
inner join sys.objects referenced_table on fk.referenced_object_id = referenced_table.object_id
inner join sys.objects constraint_object on fk.constraint_object_id = constraint_object.object_id
where referenced_table.name = #table_name
and referencing_table.name != referenced_table.name
-- Loop on child table criteria, and insert them into delete table if they have records in the db
select #tmp_id = max(id) from #tmp_to_delete
while (#tmp_id >= 1)
begin
select #new_criteria = criteria, #new_table_name = table_name from #tmp_to_delete where id = #tmp_id
set #Sql = 'if exists(select top(1) * from ' + #new_table_name + ' where ' + #new_criteria + ')
insert #to_delete (criteria, table_name) values (''' + replace(#new_criteria, '''', '''''') + ''', ''' + #new_table_name + ''')'
exec (#Sql)
set #tmp_id = #tmp_id - 1
end
truncate table #tmp_to_delete
-- Move to next record
update #to_delete
set processed = 1
where id = #id
end
-- We have a list of all tables requiring deletion. Actually delete now.
select #id = max(id) from #to_delete
while (#id >= 1)
begin
select #criteria = criteria, #table_name = table_name from #to_delete where id = #id
set #Sql = 'delete from [' + #table_name + '] where ' + #criteria
if (#IsDebug = 1) print #Sql
exec (#Sql)
-- Next record
set #id = #id - 1
end
commit
end try
begin catch
-- Any error results in a rollback of the entire job
if (##trancount > 0) rollback
declare #message nvarchar(2047), #errorProcedure nvarchar(126), #errorMessage nvarchar(2048), #errorNumber int, #errorSeverity int, #errorState int, #errorLine int
select #errorProcedure = isnull(error_procedure(), N'hp_Common_Delete'),
#errorMessage = isnull(error_message(), N'hp_Common_Delete unable to determine error message'),
#errorNumber = error_number(), #errorSeverity = error_severity(), #errorState = error_state(), #errorLine = error_line()
-- Prepare error information as it would be output in SQL Mgt Studio
declare #event nvarchar(2047)
select #event = 'Msg ' + isnull(cast(#errorNumber as varchar), 'null') +
', Level ' + isnull(cast(#errorSeverity as varchar), 'null') +
', State ' + isnull(cast(#errorState as varchar), 'null') +
', Procedure ' + isnull(#errorProcedure, 'null') +
', Line ' + isnull(cast(#errorLine as varchar), 'null') +
': ' + isnull(#errorMessage, '#ErrorMessage null')
print #event
-- Re-raise error to ensure admin/job runners understand there was a failure
raiserror(#errorMessage, #errorSeverity, #errorState)
end catch
Unless you want to maintain all related queries as proposed by Chris, the ON DELETE CASCADE is by far the quickest and the most direct solution. And if you don't want it to be permanent, why don't you have some T-SQL code that will switch this option on and off like here
remove the original Tbl_A_MyFK constraint (without the ON DELETE CASCADE)
ALTER TABLE Tbl_A DROP CONSTRAINT Tbl_A_MyFK
set the constraint Tbl_A_MyFK with the ON DELETE CASCADE
ALTER TABLE Tbl_A ADD CONSTRAINT Tbl_A_MyFK FOREIGN KEY (MyFK) REFERENCES Tbl_B(Column) ON DELETE CASCADE
Here you can do your delete
DELETE FROM Tbl_A WHERE ...
drop your constraint Tbl_A_MyFK
ALTER TABLE Tbl_A DROP CONSTRAINT Tbl_A_MyFK
set the constraint Tbl_A_MyFK without the ON DELETE CASCADE
ALTER TABLE Tbl_A ADD CONSTRAINT Tbl_A_MyFK FOREIGN KEY (MyFK) REFERENCES (Tbl_B)
Go into SQL Server Management Studio and right-click the database. Select Tasks->Generate Scripts. Click Next twice. On the Options window choose set it to generate CREATE statements only, and put everything to False except for the Foreign Keys. Click Next. Select Tables and Click Next again. Click the "Select All" button and click Next then Finish and send the script to your choice of a query window or file (don't use the clipboard, since it might be a big script). Now remove all of the script that adds the tables and you should be left with a script to create your foreign keys.
Make a copy of that script because it is how you'll restore your database to its current state. Use a search and replace to add the ON DELETE CASCADE to the end of each constraint. This might vary depending on how your FKs are currently set up and you might need to do some manual editing.
Repeat the script generation, but this time set it to generate DROP statements only. Be sure to manually remove the table drops that are generated. Run the drops, then run your edited creates to make them all cascade on delete. Do your deletes, run the drop script again and then run the script that you saved off at the start.
Also - MAKE A BACKUP OF YOUR DB FIRST! Even if it's just a dev database, it will save you some headache if part of the script isn't quite right.
Hope this helps!
BTW - you should definitely do some testing with your full test data as another poster suggested, but I can see why you might not need that for initial development. Just don't forget to include that as part of QA at some point.
Kevin post is incomplete, his t-sql sp only prints the command, to execute these command, before last end add this
DECLARE #commandText VARCHAR(8000)
DECLARE curDeletes CURSOR FOR
select 'delete from [' + table_name + '] where ' + criteria from #to_delete order by id desc
OPEN curDeletes
FETCH NEXT FROM curDeletes
INTO
#commandText
WHILE(##FETCH_STATUS=0)
BEGIN
EXEC (#commandText)
FETCH NEXT FROM curDeletes INTO #commandText
END
CLOSE curDeletes
DEALLOCATE curDeletes
I usually just hand write the queries to delete the records I don't want and save that as a .sql file for future reference. The pseudocode is:
select id's of records from the main table that I want to delete into a temp table
write a delete query for each related table which joins to the temp table.
write a delete query for the main table joining to my temp table.
My suggestion is to go ahead and write a script that will add the on delete cascade to each relationship in the database while exporting a list of modified relationships. Then you can reverse the process and remove the on delete cascade command on each table in the list.
Personally if you are going to leave the records in production, I would also leave them in development. Otherwise you may write code that works fine when the recordset is small but times out when faced with the real recordset.
But if you are determined to do this, I would copy the id field of the records you want to dete from the main table first to a work table. Then I would take each related table and write a delete joining to that worktable to only delete those records. Finish up with the parent table. Make sure this ia written in a script and saved so the next time you want to do a similar thing to your test data, you can easily run it without having to figure out what are the reated tables that need records deleted from them.
Taking the accepted answer a bit further, I had the need to do this across tables in different schemas. I have updated the script to include schema in the outputted delete scripts.
CREATE PROCEDURE usp_delete_cascade (
#base_table_schema varchar(100), #base_table_name varchar(200), #base_criteria nvarchar(1000)
)
as begin
-- Expects the name of a table, and a conditional for selecting rows
-- within that table that you want deleted.
-- Produces SQL that, when run, deletes all table rows referencing the ones
-- you initially selected, cascading into any number of tables,
-- without the need for "ON DELETE CASCADE".
-- Does not appear to work with self-referencing tables, but it will
-- delete everything beneath them.
-- To make it easy on the server, put a "GO" statement between each line.
declare #to_delete table (
id int identity(1, 1) primary key not null,
criteria nvarchar(1000) not null,
table_schema varchar(100),
table_name varchar(200) not null,
processed bit not null,
delete_sql varchar(1000)
)
insert into #to_delete (criteria, table_schema, table_name, processed) values (#base_criteria, #base_table_schema, #base_table_name, 0)
declare #id int, #criteria nvarchar(1000), #table_name varchar(200), #table_schema varchar(100)
while exists(select 1 from #to_delete where processed = 0) begin
select top 1 #id = id, #criteria = criteria, #table_name = table_name, #table_schema = table_schema from #to_delete where processed = 0 order by id desc
insert into #to_delete (criteria, table_schema, table_name, processed)
select referencing_column.name + ' in (select [' + referenced_column.name + '] from [' + #table_schema + '].[' + #table_name +'] where ' + #criteria + ')',
schematable.name,
referencing_table.name,
0
from sys.foreign_key_columns fk
inner join sys.columns referencing_column on fk.parent_object_id = referencing_column.object_id
and fk.parent_column_id = referencing_column.column_id
inner join sys.columns referenced_column on fk.referenced_object_id = referenced_column.object_id
and fk.referenced_column_id = referenced_column.column_id
inner join sys.objects referencing_table on fk.parent_object_id = referencing_table.object_id
inner join sys.schemas schematable on referencing_table.schema_id = schematable.schema_id
inner join sys.objects referenced_table on fk.referenced_object_id = referenced_table.object_id
inner join sys.objects constraint_object on fk.constraint_object_id = constraint_object.object_id
where referenced_table.name = #table_name
and referencing_table.name != referenced_table.name
update #to_delete set
processed = 1
where id = #id
end
select 'print ''deleting from ' + table_name + '...''; delete from [' + table_schema + '].[' + table_name + '] where ' + criteria from #to_delete order by id desc
end
exec usp_delete_cascade 'schema', 'RootTable', 'Id = 123'
exec usp_delete_cascade 'schema', 'RootTable', 'GuidId = ''A7202F84-FA57-4355-B499-1F8718E29058'''
Expansion of croisharp's answer to take triggers into consideration, i.e. schema-aware solution that disables all affecting triggers, deletes rows, and enables the triggers.
CREATE PROCEDURE usp_delete_cascade (
#base_table_schema varchar(100),
#base_table_name varchar(200),
#base_criteria nvarchar(1000)
)
as begin
-- Expects the name of a table, and a conditional for selecting rows
-- within that table that you want deleted.
-- Produces SQL that, when run, deletes all table rows referencing the ones
-- you initially selected, cascading into any number of tables,
-- without the need for "ON DELETE CASCADE".
-- Does not appear to work with self-referencing tables, but it will
-- delete everything beneath them.
-- To make it easy on the server, put a "GO" statement between each line.
declare #to_delete table (
id int identity(1, 1) primary key not null,
criteria nvarchar(1000) not null,
table_schema varchar(100),
table_name varchar(200) not null,
processed bit not null,
delete_sql varchar(1000)
)
insert into #to_delete (criteria, table_schema, table_name, processed) values (#base_criteria, #base_table_schema, #base_table_name, 0)
declare #id int, #criteria nvarchar(1000), #table_name varchar(200), #table_schema varchar(100)
while exists(select 1 from #to_delete where processed = 0) begin
select top 1 #id = id, #criteria = criteria, #table_name = table_name, #table_schema = table_schema from #to_delete where processed = 0 order by id desc
insert into #to_delete (criteria, table_schema, table_name, processed)
select referencing_column.name + ' in (select [' + referenced_column.name + '] from [' + #table_schema + '].[' + #table_name +'] where ' + #criteria + ')',
schematable.name,
referencing_table.name,
0
from sys.foreign_key_columns fk
inner join sys.columns referencing_column on fk.parent_object_id = referencing_column.object_id
and fk.parent_column_id = referencing_column.column_id
inner join sys.columns referenced_column on fk.referenced_object_id = referenced_column.object_id
and fk.referenced_column_id = referenced_column.column_id
inner join sys.objects referencing_table on fk.parent_object_id = referencing_table.object_id
inner join sys.schemas schematable on referencing_table.schema_id = schematable.schema_id
inner join sys.objects referenced_table on fk.referenced_object_id = referenced_table.object_id
inner join sys.objects constraint_object on fk.constraint_object_id = constraint_object.object_id
where referenced_table.name = #table_name
and referencing_table.name != referenced_table.name
update #to_delete set
processed = 1
where id = #id
end
select 'print ''deleting from ' + table_name + '...''; delete from [' + table_schema + '].[' + table_name + '] where ' + criteria from #to_delete order by id desc
DECLARE #commandText VARCHAR(8000), #triggerOn VARCHAR(8000), #triggerOff VARCHAR(8000)
DECLARE curDeletes CURSOR FOR
select
'DELETE FROM [' + table_schema + '].[' + table_name + '] WHERE ' + criteria,
'ALTER TABLE [' + table_schema + '].[' + table_name + '] DISABLE TRIGGER ALL',
'ALTER TABLE [' + table_schema + '].[' + table_name + '] ENABLE TRIGGER ALL'
from #to_delete order by id desc
OPEN curDeletes
FETCH NEXT FROM curDeletes INTO #commandText, #triggerOff, #triggerOn
WHILE(##FETCH_STATUS=0)
BEGIN
EXEC (#triggerOff)
EXEC (#commandText)
EXEC (#triggerOn)
FETCH NEXT FROM curDeletes INTO #commandText, #triggerOff, #triggerOn
END
CLOSE curDeletes
DEALLOCATE curDeletes
end
after select you have to build and execute the actual delete
declare #deleteSql nvarchar(1200)
declare delete_cursor cursor for
select table_name, criteria
from #to_delete
order by id desc
open delete_cursor
fetch next from delete_cursor
into #table_name, #criteria
while ##fetch_status = 0
begin
select #deleteSql = 'delete from ' + #table_name + ' where ' + #criteria
--print #deleteSql
-- exec sp_execute #deleteSql
EXEC SP_EXECUTESQL #deleteSql
fetch next from delete_cursor
into #table_name, #criteria
end
close delete_cursor
deallocate delete_cursor
Post here a script that will work with foreign keys contain more than one column.
create procedure usp_delete_cascade (
#TableName varchar(200), #Where nvarchar(1000)
) as begin
declare #to_delete table (
id int identity(1, 1) primary key not null,
criteria nvarchar(1000) not null,
table_name varchar(200) not null,
processed bit not null default(0),
delete_sql varchar(1000)
)
DECLARE #MyCursor CURSOR
declare #referencing_column_name varchar(1000)
declare #referencing_table_name varchar(1000)
declare #Sql nvarchar(4000)
insert into #to_delete (criteria, table_name) values ('', #TableName)
declare #id int, #criteria nvarchar(1000), #table_name varchar(200)
while exists(select 1 from #to_delete where processed = 0) begin
select top 1 #id = id, #criteria = criteria, #table_name = table_name from #to_delete where processed = 0 order by id desc
SET #MyCursor = CURSOR FAST_FORWARD
FOR
select referencing_column.name as column_name,
referencing_table.name as table_name
from sys.foreign_key_columns fk
inner join sys.columns referencing_column on fk.parent_object_id = referencing_column.object_id
and fk.parent_column_id = referencing_column.column_id
inner join sys.columns referenced_column on fk.referenced_object_id = referenced_column.object_id
and fk.referenced_column_id = referenced_column.column_id
inner join sys.objects referencing_table on fk.parent_object_id = referencing_table.object_id
inner join sys.objects referenced_table on fk.referenced_object_id = referenced_table.object_id
inner join sys.objects constraint_object on fk.constraint_object_id = constraint_object.object_id
where referenced_table.name = #table_name
and referencing_table.name != referenced_table.name
OPEN #MyCursor
FETCH NEXT FROM #MYCursor
INTO #referencing_column_name, #referencing_table_name
WHILE ##FETCH_STATUS = 0
BEGIN
PRINT #referencing_column_name
PRINT #referencing_table_name
update #to_delete set criteria = criteria + ' AND '+#table_name+'.'+#referencing_column_name+'='+ #referencing_table_name+'.'+#referencing_column_name
where table_name = #referencing_table_name
if(##ROWCOUNT = 0)
BEGIN
--if(#id <> 1)
--BEGIN
insert into #to_delete (criteria, table_name)
VALUES( ' LEFT JOIN '+#table_name+' ON '+#table_name+'.'+#referencing_column_name+'='+ #referencing_table_name+'.'+#referencing_column_name+ #criteria,
#referencing_table_name
)
--END
--ELSE
--BEGIN
--insert into #to_delete (criteria, table_name)
--VALUES( ' LEFT JOIN '+#table_name+' ON '+#table_name+'.'+#referencing_column_name+'='+ #referencing_table_name+'.'+#referencing_column_name,
--#referencing_table_name
--)
--END
END
FETCH NEXT FROM #MYCursor
INTO #referencing_column_name, #referencing_table_name
END
CLOSE #MyCursor
DEALLOCATE #MyCursor
update #to_delete set
processed = 1
where id = #id
end
--select 'print ''deleting from ' + table_name + '...''; delete from [' + table_name + '] where ' + criteria from #to_delete order by id desc
--select id, table_name, criteria, #Where from #to_delete order by id desc
select #id = max(id) from #to_delete
while (#id >= 1)
begin
select #criteria = criteria, #table_name = table_name from #to_delete where id = #id
set #Sql = 'delete [' + #table_name + '] from [' + #table_name + '] ' + #criteria+' WHERE '+#Where
exec (#Sql)
PRINT #Sql
-- Next record
set #id = #id - 1
end
end
This script has two issues:
1. You must indicate the condition 1=1 in order to delete all table base.
2. This creates the direct relations with the base table only. If the final table has another table parent relation, the the delete fail
DELETE FROM [dbo].[table2] WHERE TableID in (select [ID] from [dbo].[table3] where 1=1)
If table2 has a parent relation table1