Cascading deletes - Which is better
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.
DRI(declarative referential integrity) triggers are used when Cascade Deletes and Updates cannot be implemented in the RDBMS(relational database management system) as in SQL Server 7.0 and below. In SQL Server 2000 using Cascade Delete and Cascade Update is the way to go. The reason is reliability related because ...Is Cascading deletes prefered to deleting thru a stored procedure?
I have a situation in which I have three tables - 'Table1', 'Table2' and 'Table3'.
'Table1' is a primary table for 'Table2' so that the the primary key of 'Table1' is a foreign key in 'Table2'. In the same way, 'Table1' is also the primary table for 'Table3'.
If I delete a row in 'Table1' then I could automatically let SQL Server also delete the related rows in 'Table2' and 'Table3' through 'cascading delete' option. Or I could run a trigger or stored procedure for deleting related rows in 'Table2' and 'Table3'. Which of these methods would be quicker? Also would cascading deletes option a...on delete cascade?
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I'm new to Sybase SQL Server 11 and I'm wondering whether
there is any possibility to perform a cascading delete
in a master-detail-relationship using a foreign key constraint?
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Does anyone know how to implement cascade delete within ASE on tables
with foreign keys?
If so please help me! I know that ASA has this capability but I can not
find anything in ASE to support it.
Here is my email if you have an answer
ASE does not support declarative cascading deletes through referential
If you want to do cascading deletes, you will have to write triggers to
foreign keys, rather than using the constraints.
Rich and Peg wrote:
> Does anyone know how to implement cascade dele...Cascading delete
In my consolidated database I have a foreign key between two tables with the
cascading delete integrity constraint applied.
The two tables are replicated (in their entirety) to a remote database. In
the remote database should I have the delete integrity constraint applied in
the foreign key between the two tables? If a record is deleted from table A
in the consolidated database and this cascades and deletes a record in table
B, won't the individual delete statements from the transaction log be
applied to the remote database thus removing the need for the "cascade" to
In SQL Central, how do I set sqlanywhere to enforce referential integrety
delete all foreign keys when a record is deleted?
Thanks for any help,
>In SQL Central, how do I set sqlanywhere to enforce referential integrety
>and delete all foreign keys when a record is deleted?
To create a foreign key you can click on the "Add foreign Key" line
to start a fkey creation wizard. To change the properties of an
existing foreign key definition, Right click on the foreign key and
choose Properties. Click the 'Integrity' tab. Under "de...On delete cascade
I faced this issue when using ON DELETE CASCADE functionality. Please
let me if this can be termed as a bug.
create table test(
primary key (num)
create table test_assoc(
primary key(num1, num2),
foreign key num1 references test(num) on delete cascade, *-- NOTE:
CASCADE is specified here.*
foreign key num2 references test(num) on delete cascade, );
My assumption was if i delete any row from the test table, then all the
rows which are affected by this will get deleted automatically from the
tes...Delete on cascade
I have a problem with the speed of a delete on a table that use cascades
I use ASA 126.96.36.1993
I have a table (tb_a). It has 100 records.
This table is referenced by 16 other tables. (tb_b)
Some of these tables are referenced by other tables.(tb_c)
Some of these referenced tables are referenced by other tables. (tb_d)
Sometimes, tables are referencing other tables directly ex : tb_a is
referenced by tb_d
When I make a delete on tb_a, it takes 30 sec. to make the delete. The
delete is indexed as I delete on the primary key from tb_a.
For tb_b, tb_c, tb_c, There ...delete cascade
I'm trying to add delete cascade to an already-existing table via ISQL. I'm
getting a syntax error:
alter table carrier on delete cascade;
Error = syntax error near 'on'
Should I be able to do this?
I'm running on Windows 2000 Pro, SQLAnywhere 5.5.03, using DBENG50.EXE.
It should be something like:
alter table carrier drop foreign key fk1
alter table carrier add foreign key fk1 references ... etc ... on delete
Then when the row in the fk1 table is deleted the row in the "carrier" table
will be deleted also.
http://www...CASCADE ON DELETE
Just a quick question: will ASE 12.5 support CASCADE ON DELETE on table
I'm trying to implement cascading deletes in Sybase via a trigger. I know I
can't just specify this when I create the foreign key constraint. So, my
question is this, which will fire first, the RI or the trigger? If it's the
former, then I won't be able to delete any children because the parent will
exist. Is there a clean workaround if this is the case?
---== Posted via the PFCGuide Web Newsreader ==---
Don't use the constraints. Use only the triggers for your RI.
Arthur Lan...Cascading Deletes
In PowerDesigner 9.5.2, is it possible to have all relationships in the PDM
which have cascading deletes highlighted in a different color than the
others. I'm hoping there is a way other than manually changing the color on
If you can handle a little VB Script writing, you can do it.
There are a few sample scripts to start with. What you will need to do is:
Spin through all of the references.
For each, if the type is on delete cascade, then set the color attribute to
It really shouldn't be a lot of coding. If you need help, post back here
Thanks. So I understand that there is currently no cascading deletes in MS
SQL Server and you implement it using triggers or similar.
Correct. There is a LOT of stuff missing from MS SQL Server. You will
be much happier with SQL Anywhere.
On Tue, 26 Dec 2000 11:23:39 -0800, "Anand" <email@example.com>
>Thanks. So I understand that there is currently no cascading deletes in MS
>SQL Server and you implement it using triggers or similar.
PowerDesigner Version 188.8.131.528 and MS SQL 7.0 SP3.
I need to be able to allow for Cascading deletes and updates.
I see two problems at this point:
One is the current code in the DBMS properties for Relationship Create is
[%USE_SP_FKEY%?[execute ]sp_foreignkey %TABLE%, %PARENT%, %FKEYCOLUMNS%
:alter table [%QUALIFIER%]%TABLE%
add [constraint %CONSTNAME%] foreign key (%FKEYCOLUMNS%)
references [%PQUALIFIER%]%PARENT%[ (%CKEYCOLUMNS%)]]
In order for it to place the correct code I believe I need to have the