Numerical sequence generation for automatic key creation

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2
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3answers
6k views

How to use 2 auto increment columns in MySQL phpmyadmin

Is it possible to use 2 auto increment values ? One starting from 0 Another starting from 4000400 Please help me
4
votes
1answer
3k views

MySQL get next unique value without auto increment

I have an MySQL database (InnoDB) that I'm developing for tracking Work Orders at my organization. There are multiple 'sites', and each site has work order numbers starting at 100. WorkorderID ...
0
votes
2answers
3k views

MySQL - Autoincrement does not increment sequentally if last row was deleted

I have a table which contains an auto incremented primary key id. If I delete the last row (highest id, for exampe id = 6) and insert a new row, the new id starts at 7. Which paramater I have to ...
15
votes
2answers
16k views

Is MySql's LAST_INSERT_ID() function guaranteed to be correct?

When I do a single row INSERT to a table that has an AUTO_INCREMENT column I'd like to use the LAST_INSERT_ID() function to return the new AUTO_INCREMENT'ed value stored for that row. As many SQL ...
5
votes
2answers
965 views

What Is The Point of a Primary Key?

Why do I need to have a primary key on my database for it to function correctly? In every tutorial I read, you need to make the id key the primary key. What does the primary key do differently than ...
4
votes
5answers
2k views

using IDENTITY column with increment -1

I need to run a sql server logging db with 2 main tables in 2 seperate datacentres writing to both at the same time. I had the idea of restoring the db to the new datacentre and then reseeding the ...
3
votes
1answer
2k views

Fixing table structure to avoid `Error: duplicate key value violates unique constraint`

I have a table which is created this way: -- -- Table: #__content -- CREATE TABLE "jos_content" ( "id" serial NOT NULL, "asset_id" bigint DEFAULT 0 NOT NULL, ... "xreference" varchar(50) ...
3
votes
1answer
675 views

User autoincrement ID for username

I want to automatically create user's, which all have a unique ID. Now here's the problem. If two users are created at exactly the same nanosecond, it may not cause problems. Thus, what i do now is: ...
3
votes
1answer
3k views

How do I make MySQL auto increment in random order?

I have a table that contains several keys into other tables (where each key is comprised of multiple columns). I would like to create a new column for each key that would be an integer such that ...
2
votes
1answer
450 views

Why does auto increment jumps by more than the number of rows inserted?

I am very perturbed by this weird behaviour I am seeing in the auto_increment value recorded in the bidID of a Bids table after performing bulk insertion using a stored procedure: INSERT INTO Bids ...
2
votes
2answers
2k views

Reset IDENTITY value

I have a table with an IDENTITY column. While developing I delete the rows from time to time and add them again. But the IDENTITY values always kept increasing and didn't start from 1 when I added ...
1
vote
1answer
168 views

MySQL auto_increment delivers different primary key in MyISAM and InnoDB

I have a table with auto incremental primary key. If I want to change a row and add new rows I got different primary keys depending on engine MyISAM and InnoDB. The original table is: pk.. ...