does PHP support foreign key and Rollback?yes or not.if not
then why. how will you done these concept in php?
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 |
What are the different types of statements that are present in php?
Is it possible multiple inheritance in php?
What are some of the advanced features of php?
Is the cookies are available on cross domain?
How to insert a line break in php string?
What are the different functions in sorting an array?
Tell me how to initiate a session in php?
Explain some most commonly use string functions in php?
What is difference between md5 and SHA256?
How to remove duplicate values from php array?
What is the difference between md5(), crc32() and sha1() crypto on php?
Which programming language does php resemble?