I am looking to delete a single row from a relatively small table. Unfortunately, there is a foreign key relationship between this table and a much much larger table. The checking of this foreign key when I am deleting this row seems to significantly impact the performance of the operation. Previously there was an index on this larger table that helped this query run. This index has been dropped to improve the performance of a more frequently executed operation.
Is there a way I can use a hint or something to stop SQL checking this foreign key when deleting the row? I am certain that there are no associated rows in the larger table.
I have read elsewhere that I could disable the foreign key, perform the delete, then enable the foreign key. This delete statement is not a one off process and could happen in the normal operation of the application so I don't really know what the implications of doing this are.
Is there any easy way to truncate a table which has a foreign key restraint? I want to override the default behavior which is to not allow truncate of parent tables. I want to be able to temperarily remove the contraint so I can truncate the temple, how do you do this?
Background: Am working on completing an ORM that can not only handles CRUD actions -- but that can also updates the structure of a table transparently when the class defs change. Reason for this is that I can't get the SQL scripts that would work for updating a software on SqlServer to be portable to other DBMS systems. Doing it by code, rather than SQL batch has a chance of making cross-platform, updateable, software...
Anyway, because it needs to be cross-DBMS capable, the constraints are that the system used must work for the lowest common denominator....ie, a 'recipe' of steps that will work on all DBMS's.
The Problem: There might be simpler ways to do this with SqlServer (all ears :-) - just in case I can't make it cross platform right now) but, with simplistic DBMS's (SqlLite, etc) there is no way to ALTER table once formed: one has to COPY the Table to a new TMP name, adding a Column in the process, then delete the original, then rename the TMP to the original name.
This appears possible in SqlServer too --...as long as there are no CASCADE operations. Truncate table doesn't seem to be the solution, nor drop, as they all seem to trigger a Cascade delete in the Foreign Table.
So -- please correct me if I am wrong here -- it appears that the operations would be along the lines of: a) Remove the Foreign Key references b) Copy the table structure, and make a new temp table, adding the column c) Copy the data over d) Add the FK relations, that used to be in the first table, to the new table e) Delete the original f) Done?
The questions are: a) How does one alter a table to REMOVE the Foreign Key References part, if it has no 'name'. b) Anyone know of a good clean way to get, and save these constraints to reapply them to the new table. Hopefully with some cross platform ADO.NET solution? GetSchema etc appears to me to be very dbms dependant? c) ANY and all tips on things I might run into later that I have not mentioned, are also greatly appreciated.
I need to delete records from a table (Table1) which has a foreign key column in a related table (Table2).
Table1 columns are: table1Id; Name. Table2 columns include Table2.table1Id which is the foreign key to Table1.
What is the syntax to delete records from Table1 using Table1.Name='some name' and remove any records in Table2 that have Table2.table1Id equal to Table1.table1Id?
How to delete records from multiple tables if main table’s entity is deleted as constraints is applied on all..There is this main table called Organization or TblOrganization.and this organization have branches which are in Brach table called tblBranch and this branch have multiple applications let say tblApplication and these application are used by multiple users called tblUsers.What I want is: when I delete the Organization All branches, application and users related to it must be deleted also.How I can apply that on a button click in asp.net web forms..Right now this is my delete function which is very simple
Public void Delete(int? id){ var str=”DELETE FROM tblOrganization WHERE organizationId=”+ id ; } And My tables LOOK LIKE this CREATE TABLE tblOrganization ( OrganizationId int, OrganizationName varchar(255)
Is there a way to see the locks associated with a delete statement on a table (tab1) that has 5 or 6 Foreign key relationships. Trying to understand the impact of the delete on concurrency There are several delete deadlocks on one of the foreign key tables (tab2) and the system does not delete from the table (tab2) that is throwing the delete deadlock error. Wondering about the impact of foreign keys on deletes on Tab1 on Tab2.
Didn't see anything in query analyzer that would show the actual locks. It seems to have scans or such but no lock levels etc are shown.
Does anyone have any knowledge of how to see the actual locks thrown by a given statement. The delete on Tab1 statement is very quick so using EM has proved fruitless.
Hi, How do I delete data which is a Foreign Key in another table? For example; string query = "DELETE * from user_details WHERE user_ID = '" +userID.Text+ "'; The user_ID is the Primary Key in the user_details table and also a Foreign Key in other tables. Thank you. (:
I have a SQL Mobile DB that I am having problems with deletes cascading via foreign keys to delete all child records. The DB is on a WIndows CE5 device that is running a C#.net application.
The are three tables in my DB that relate to this issue (Tests, TestRawInfo, and TestRawData). The Tests table is the main table. TestRawInfo is a child table of Tests and has a foreign key defined that references the Tests primary key (the relationship is 1:1 with the Tests table). TestRawData is a child table of TestRawInfo and has a foreign key defined that references the TestRawInfo primary key (The relationship is 1:many with the TestRawInfo table). All foreign keys are defined with a Cascade on delete. When I delete one or more records from the Tests table I expect the delete to cascade so that all child records are also deleted. Not all the data gets deleted from the TestRawData table, this results in orphan records. I only see a failure however the next time I attempt to compact the database.
Interestingly I can reproduce the problem by opening my Mobile DB in SQL 2005 on my Desktop and deleting data from the Tests table. If however, I add additional records to these tables through SQL 2005 before attempting to delete, the delete works as expected.
Do you have any ideas on what is going on here? Has any one else reported a similar issue? My current work around is to delete data directly from child tables and not rely on the foreign keys to cascade the deletes.
I have a table that contains two foreign keys of two different tables. I want to build a relationship so that when either primary keys deleted in the two tables, the record in the table should be deleted. But, SQL Server does not allow me to save the relationship, it complains that the circling delete might exist. I do not know why, how can I solve this?
Table A: ID ProductID <foreign key> CustomerID <foreign key>
Table Product ProductID <primary key>
Table Customer CustomerID <primary key>
I want to cascade delete the record in Table A when either the ProductID is deleted from Product table or the CustomerID is deleted from Customer table.
I'm trying to create relational database with some triggers in SQL Server 7.0, but it doesn't work as expected. Let's say that I have 'Office' database with two tables, 'Users' and 'UserRights' (userRights table should have much more rights, but that's not relevant for this problem):
CREATE TABLE [Users] ( [FS_Username] [nvarchar] (8) NOT NULL , [FS_Password] [nvarchar] (32) NOT NULL , CONSTRAINT [PK_Users] PRIMARY KEY NONCLUSTERED ( [FS_Username] ) ON [PRIMARY] ) ON [PRIMARY] GO
CREATE TABLE [UserRights] ( [FS_Username] [nvarchar] (8) NOT NULL , [FI_UserType] [int] NOT NULL CONSTRAINT [DF_UserRights_FI_UserType] DEFAULT (1), [FI_AllowLogin] [int] NOT NULL CONSTRAINT [DF_UserRights_FI_AllowLogin] DEFAULT (1), CONSTRAINT [PK_UserRights] PRIMARY KEY NONCLUSTERED ( [FS_Username] ) ON [PRIMARY] , CONSTRAINT [FK_UserRights_Users] FOREIGN KEY ( [FS_Username] ) REFERENCES [Users] ( [FS_Username] ) ) ON [PRIMARY] GO
Foreign Key CONSTRAIN above is created by adding both tables to the diagram and defining relationship between these two tables FS_Username field, where 'Enable relationship for INSERT and UPDATE' option is turned ON. You can easily see this if you create diagram youself and insert these two tables in it. Next to this, I created two triggers that should handle inserting/deleting rows in UserRights table as consequence of inserting/deleting rows in Users table:
CREATE TRIGGER InsertUserRights ON Users FOR INSERT AS BEGIN INSERT INTO UserRights (FS_Username) (SELECT FS_Username FROM Inserted) END
CREATE TRIGGER DeleteUserRights ON Users FOR DELETE AS BEGIN DELETE UserRights WHERE FS_Username IN (SELECT FS_Username FROM Users) END
Now, when (manually) I insert row in Users table, UserRights table gets updated accordingly. HOWEVER, when I try to delete one or more entries from Users table, I get error report. For example, if you try to execute following two commands:
Insert Into Users (FS_Username, FS_Password) VALUES ('John', 's')
Delete from Users
... first command will succede, but second one will fail with message:
DELETE statement conflicted with COLUMN REFERENCE constraint 'FK_UserRights_Users'. The conflict occurred in database 'Office', table 'UserRights', column 'FS_Username'. The statement has been terminated.
Does anyone know how to resolve this problem without loosing constrains and triggers ? (If I turn off 'Enable relationship for INSERT and UPDATE' option for relationship, things will work fine, but than I can make inconsistent data in UserRights table).
there are two tables involve in replication let say table1 and replicated table is also rep.table1.
we are not deleting records physically in table1 so only a bit in table1 has true when u want to delete a record but the strange thing is that replication agaent report that this is hard delete operation on table1 so download and report hard delete operation and delete the record in replicated table which is very crucial.
plz let me know where am i wrong and how i put it into right way.
there is no triggers on published tables and noother trigger is created on published table.
I'm trying to clean up a database design and I'm in a situation to where two tables need a FK but since it didn't exist before there are orphaned records.
Tables are:
Brokers and it's PK is BID
The 2nd table is Broker_Rates which also has a BID table.
I'm trying to figure out a t-sql statement that will parse through all the recrods in the Broker_Rates table and delete the record if there isn't a match for the BID record in the brokers table.
I know this isn't correct syntax but should hopefully clear up what I'm asking
The requirement is: I should allow single row delete from a table but not bulk delete. An audit table should get updated if there is any single delete or single update. So I wrote the triggers as follows: for single and bulk delete
ALTER TRIGGER [dbo].[TRG_Delete_Bulk_tbl_attendance] ON [dbo].[tbl_attendance] AFTER DELETE AS
[code]...
When I try to run the website, the database error I am getting is:Transaction count after EXECUTE indicates that a COMMIT or ROLLBACK TRANSACTION statement is missing. Previous count = 0, current count = 1.
I need to implement my cascading deletes on a SQL database. Is it better (performance/reliablility-wise) to use the Foreign Key Cascading Deletes or to just write my own triggers to do the deletes?I was hoping someone had experimented and found which works best.
I want to make a query, stored procedure, or whatever which will only display the primary key where there does no exist a foreign key in linked table.For example. If I had two tables with a one to many relationship.A [Computer] has one or more [Hard Drives]. I want to select only those computers which do not have a Hard Drive(s) associated with them. That is, show all computers where the Computer_ID field in the [Hard Drives] table does not exist. This seems simple but I'm drawing a blank here.
Previously same records exists in table having primary key and table having foreign key . we have faced 7 records were lost from primary key table but same record exists in foreign key table.
Here is my issue I am new to 2005 sql server, and am trying to take my old data which is exported to a txt file and import it to tables in sql. The older database is non relational, and I had made several exports for the way I want to build my tables. I built my packages fine and everything is working until I start building relationships. I remove my foreign key and the table with the primary key will get updated for the package again. I need to update the data daily into sql, and once in it will only be update from the package until the database is moved over.
It will run and update with a primary key until I add a foreign key to another database.
Here is my error when running the package when table 2 has a foreign key.
[Execute SQL Task] Error: Executing the query "TRUNCATE TABLE [consumer].[dbo].[Client] " failed with the following error: "Cannot truncate table 'consumer.dbo.Client' because it is being referenced by a FOREIGN KEY constraint.". Possible failure reasons: Problems with the query, "ResultSet" property not set correctly, parameters not set correctly, or connection not established correctly.
it is attributed ? Hi everyone, My table contains columns that are goreign keys to other tables. How can i tell to which table/column each fk is attributed ? Thanks
Between all this tables exist one or more foreign key restriction but I don't know them. However I know than exist a row in the SYSOBJECTS (system table) per each one of the foreing key restriction, using this information I want to build a query than back to me something like this:
Type Table1 Field1 Table2 Field2 -------------------------------------------------------------------------------------------------------- FK Orders fk_Client Clients id_Client FK DetailOrders fk_Order Orders id_OrderFK
I was thinking of adding tables to ASPNetDB.mdf and have one of those tables have column userid as a foreign key from aspnet_Users When I try to create relationship in Diagram, I get error saying that "data typ properties does not match" userid in aspNet_Users is uniqueidentifier and userid (fk) in new table is int What should I use, should I do that at all?
I have created two tables in phpMyAdmin 3.5.8.1. comments which stores comments users post on a website and registration which stores a users registration details (username, password, e-mail etc, etc).
I want to add the username field from the registration table as a foreign key to the comments table. How do I do this in phpMyAdmin?
use default pubs database in sqlserver2000. use authors table and publishers table.
Write a query to list first name, last of all authors and name of the publisher (if any) present in the same city as the author. If no publisher is present in the city where the author is located then the column should contain a NULL value. If there is more than one publisher in the city where the author is located, then the details of the author are to be repeated for each publisher.
but there is no field match between authors table and publishers table.
There is itemlookup table, which stores item number and itemdescription. Also there is a child table, pricehistory, of theitemlookup table, which stores different prices and different dateranges. So it is one-to-many relationship. (Price can be stored morethan one with a different date range)And there is another table RequestItem that stores the foreign key ofthe itemlookup table to show the information of the itemlookup table.Then how do I know later which date range of the price was stored inthe RequestItem table? Since I only keep the foreign key of theitemlookup table, it will be impossible to keep track of the row of thepricehistory table if there are more than one data existed in thepricehistory table.Will it be a valid table structure to create a column for the foreignkey of the pricehistory in RequestItem table or any other ways tohandle this issue?
Here ID is the foreign key. I was wondering if there was a way to update tables with foreign keys. Searching for stuff gave me something like update cascade. Can somebody please elaborate on that?
I've just found out about the concept that a table should only be references by foreign keys a maximum of 253 times throughout the database. I was hoping someone could give me a better idea of the dangers of disregarding this recommendation.
In our database, we have a Users table, which contains all of the users of a given system. In nearly every other table in our database, we have a field to indicate which user created the record. This is a reference back to the Users table. But as the number of tables has grown, we've surpassed that 253 limit. All I can tell, practically, is that I can no longer delete from the Users table. The query will fail, telling me the query optimizer ran out of memory, and that I should simplify my query.
The Users table is the only table that even comes close to this number of foreign key references. I don't even mind being unable to delete from the table. I'm mostly wondering if there are other problems with my design that will cause issues?
Is there a better way to keep track of who created a record in the database? Is it bad design to reference my Users table in so many places?
I have two tables as below. I want to update a quote and change the item for which it is for. So I want to do an update statement to change the cat_ref that the quote is for. However, when I do this I get a foreign key conflict with cat_ref in the item table. How do I get around this? Thanks
