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From:Alec.Cawley Date:August 24 2005 10:38am
Subject:Re: INSERT IGNORE Doesn't Seem To Work
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The insert will only be bounced where you specify the columns as unique. 
Thus you need either separate UNIQUE indexes on Name and Value, if you 
want them to be individually unique, or a single joint UNIQUE index if you 
want them to be jointly unique but separately duplicable. The INSERT 
command only checks columns that is instructed are to be unique.

The purpose of the IGNORE modifier is simply to ignore the error produced 
when a duplicate occurs.

        Alec




Hal Vaughan <hal@stripped> 
24/08/2005 07:47
Please respond to
hal@stripped


To
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Subject
INSERT IGNORE Doesn't Seem To Work






I may have a misunderstanding of this, but as I have been told, if I have 
a 
table with 3 columns, Idx (an Index column, unique, auto-increment), Name, 

Value (both varchar), and I try a command like this:

INSERT IGNORE INTO myTable SET Name = "Variable1", Value = "100";
or
INSERT IGNORE INTO myTable (Name, Value) VALUES("Variable1", "100");

AND I already have a row with the matching Name and Value columns matching 
in 
value, that MySQL will detect that and not insert the redundant values. 
I've 
also tried this without a unique, auto-increment column, just trying to 
insert by specifying values for all 3 columns that already match an 
existing 
row, and it still doesn't work.

I thought the IGNORE keyword was intended to be used to prevent 
duplicating 
values, and that it matched the values in the INSERT statement (even if 
not 
all columns in the table were given a value) against the ones in the table 

and would NOT INSERT the row if it matched.

I'm using MySQL 4.023 on Debian Linux (installed through apt-get, not 
through 
downloading).

So this brings up a few questions: 1) Am I doing something wrong?  2) Is 
this 
what INSERT IGNORE is supposed to do -- if not, what does it do?, and 3) 
If 
this isn't what INSERT IGNORE does, how can I do what I *thought* it did 
-- 
insert only if the value doesn't already exist?

Thanks!

Hal

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Thread
INSERT IGNORE Doesn't Seem To WorkHal Vaughan24 Aug
  • Re: INSERT IGNORE Doesn't Seem To WorkJohan Höök24 Aug
  • Re: INSERT IGNORE Doesn't Seem To WorkAlec.Cawley24 Aug
  • Re: INSERT IGNORE Doesn't Seem To WorkHal Vaughan24 Aug
    • Re: INSERT IGNORE Doesn't Seem To WorkSGreen24 Aug
    • Re: INSERT IGNORE Doesn't Seem To WorkAlec.Cawley25 Aug
      • Re: INSERT IGNORE Doesn't Seem To WorkHal Vaughan26 Aug
        • Re: INSERT IGNORE Doesn't Seem To WorkPeter Brawley26 Aug