Re: BUG #3965: UNIQUE constraint fails on long column values - Mailing list pgsql-bugs

Juho Saarikko wrote:
> While I didn't test, I'd imagine that this would also mean that any attempt
> to insert such values to an already unique column would fail.

Works here in 8.3:

    test=> create table test (x text unique);
    NOTICE:  CREATE TABLE / UNIQUE will create implicit index "test_x_key" for table "test"
    CREATE TABLE
    test=> insert into test values (repeat('a', 50000));
    INSERT 0 1

Even this works:

    test=> insert into test values (repeat('a', 50000) || 'b');

I believe the index only indexes 8192 bytes but checks the heap for
longer values to check the full length.

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  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
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