Solved

best way to get next ID in database table

Posted on 2010-09-13
8
1,026 Views
Last Modified: 2012-05-10
Hi Experts,
I want to save the data of a record to the database (which has many rows).  I will need to do this in a transaction.  I want to get what the next ID should be (without using auto-incrementing rows).  So I want some way of locking the table so that I can do the following:
- Lock the table
- Get the next logical ID I should use
- insert my rows
- unlock the table

Is there a way to do this without using database-specific calls?
I could do something like this:
while(true)  {
   while (lock table does not exist)  {
      create lock table
      query other table for max ID
      insert using MaxID + 1
      delete lock table
      return
   }
   sleep (2000)
}
0
Comment
Question by:thready
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
  • 2
  • 2
8 Comments
 
LVL 3

Expert Comment

by:ghayasurrehman
ID: 33663455
insert into table () value ()
select @@scopeidenty


it will return the current id
0
 
LVL 1

Author Comment

by:thready
ID: 33663489
isn't this database-specific?
0
 
LVL 86

Expert Comment

by:jkr
ID: 33663492
>>Is there a way to do this without using database-specific calls?

If you can guarantee that no other process will be accessing the DB during such an operation - yes. If not, I cannot imagine any way that is not specific to the DB. However, if you can use ODBC (http://en.wikipedia.org/wiki/Open_Database_Connectivity), you can reduce the 'specificness' of that.
0
Get Database Help Now w/ Support & Database Audit

Keeping your database environment tuned, optimized and high-performance is key to achieving business goals. If your database goes down, so does your business. Percona experts have a long history of helping enterprises ensure their databases are running smoothly.

 
LVL 3

Expert Comment

by:ghayasurrehman
ID: 33663502
yes, this is for MS sql server
0
 
LVL 1

Author Comment

by:thready
ID: 33663539
and wouldn't it depend on knowing how columns were created (like auto-incrementing) ?
0
 
LVL 1

Author Comment

by:thready
ID: 33664258
If I must use database-specific, would you know how to do it with Postgres?
0
 
LVL 86

Accepted Solution

by:
jkr earned 500 total points
ID: 33664327
0
 
LVL 1

Author Closing Comment

by:thready
ID: 33664420
gracius seignior
0

Featured Post

How Do You Stack Up Against Your Peers?

With today’s modern enterprise so dependent on digital infrastructures, the impact of major incidents has increased dramatically. Grab the report now to gain insight into how your organization ranks against your peers and learn best-in-class strategies to resolve incidents.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Does the idea of dealing with bits scare or confuse you? Does it seem like a waste of time in an age where we all have terabytes of storage? If so, you're missing out on one of the core tools in every professional programmer's toolbox. Learn how to …
Creating and Managing Databases with phpMyAdmin in cPanel.
The viewer will learn how to use the return statement in functions in C++. The video will also teach the user how to pass data to a function and have the function return data back for further processing.
The viewer will learn how to user default arguments when defining functions. This method of defining functions will be contrasted with the non-default-argument of defining functions.

752 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question