Golgappa.net | Golgappa.org | BagIndia.net | BodyIndia.Com | CabIndia.net | CarsBikes.net | CarsBikes.org | CashIndia.net | ConsumerIndia.net | CookingIndia.net | DataIndia.net | DealIndia.net | EmailIndia.net | FirstTablet.com | FirstTourist.com | ForsaleIndia.net | IndiaBody.Com | IndiaCab.net | IndiaCash.net | IndiaModel.net | KidForum.net | OfficeIndia.net | PaysIndia.com | RestaurantIndia.net | RestaurantsIndia.net | SaleForum.net | SellForum.net | SoldIndia.com | StarIndia.net | TomatoCab.com | TomatoCabs.com | TownIndia.com
Interested to Buy Any Domain ? << Click Here >> for more details...


does PHP support foreign key and Rollback?yes or not.if not
then why. how will you done these concept in php?



does PHP support foreign key and Rollback?yes or not.if not then why. how will you done these conce..

Answer / praveen

PHP supports Foreign Keys in InnoDB Storage Engine in
version and above 4.0. It checks the foreign key referential
integrities on Delete and Select statements. If you strictly
needed the foreign keys and speed is not a concern then you
can create table structures using InnoDB Storage Engine.


Where as MyISAM Storage Engines does not allow foreign key
concept. But it will parse the table that contains foreign
keys but wont check the referential integreties. So it is
the job of the designer/programmer to check the desired key
and its dependency in multiple tables.

Let us suppose you have a field F1(primary)in Table1 and
this field is referenced in another tables denoted as (F2,
F3) in tables Table2, Table3......(as a foreign key)

and when you want to perform a DELETE operation/query based
on field F1, then
First you need to write a query to Delete the specified row
in Table1
and you also need to write a query to Delete all
dependent/referenced rows in other tables Table2, Table3...

Is This Answer Correct ?    6 Yes 0 No

Post New Answer

More PHP Interview Questions

How to create a session? How to remove data from a session?

0 Answers  


Is it possible to get the screen resolution and like with php?

1 Answers  


What is meant by pdo in php?

0 Answers  


How can we extract string 'techinterviews.com' from a string 'http://www.techinterviews.com' using regular expression in PHP?

4 Answers  


Whether session will work if we disable cookies in client browser ?

10 Answers  


What does the php error 'parse error in php - unexpected t_variable at line x' means?

0 Answers  


What is apache and php?

0 Answers  


Do you know how to declare an array in php?

0 Answers  


What is api laravel?

0 Answers  


Which operator is used to combine string values in php?

0 Answers  


What is the main difference between asp net and php?

0 Answers  


Applications written to provide a GUI shell for Unix and Linux are called

0 Answers  


Categories