Re: Duplicate data even with primary keys enabled


My postgresql version is 14.4. 

I’m aware if bug on index in older version but it beleave it fixed in version 14.4. Please check following pictures. We had pk on two columns but we had too many dublicate records on these columns.


Ctid was different

Sent from my iPhone

On 29 Oct 2022, at 7:06 PM, Samed YILDIRIM <samed(at)reddoc(dot)net> wrote:




Hi Teja,

Your columns are varchar. They may seem the same to you due to the tool you use. But, it doesn't mean they are identical. There can be leading or trailing spaces.

You can test the data on columns by md5 hashing function, example below. If their hashes are the same, it means there is a problem on the database side. Otherwise, the problem comes from the data itself or from the application writing the data into the table.

select md5(col1), md5(col2), md5(col3) from table.

Another possibility is that you hit a bug I mentioned earlier from 14.0 to 14.3.


- What version of PpstgreSQL do you use?


- Did you use CONCURRENTLY keyword while creating your index?

Best regards.

Samed YILDIRIM

On Fri, 28 Oct 2022, 23:16 Teju Jakkidi vlogs, <teja(dot)jakkidi05(at)gmail(dot)com> wrote:

Hello Jakobs,

I have provided the sample create table and inserts that we are observing. 

CREATE TABLE IF NOT EXISTS "TEST"

(

    "COL1" character varying(9) COLLATE pg_catalog."default" NOT NULL,

    "COL2" character varying(30) COLLATE pg_catalog."default" NOT NULL,

    "COL3" character varying(30) COLLATE pg_catalog."default" NOT NULL,

    "COL4" numeric(10,0) NOT NULL,

    "COL5" character varying(12) COLLATE pg_catalog."default" NOT NULL,

    "COL6" character varying(12) COLLATE pg_catalog."default" NOT NULL,

    CONSTRAINT test_pk PRIMARY KEY ("COL1", "COL2", "COL3")

)

CREATE UNIQUE INDEX IF NOT EXISTS "TEST_UNIQUE"

    ON "TEST" USING btree

    ("COL1" COLLATE pg_catalog."default" ASC NULLS LAST, "COL2" COLLATE pg_catalog."default" ASC NULLS LAST, "COL3" COLLATE pg_catalog."default" ASC NULLS LAST);

CREATE INDEX IF NOT EXISTS "TEST_INDEX"

    ON "TEST" USING btree

    ("COL1" COLLATE pg_catalog."default" ASC NULLS LAST, "COL3" COLLATE pg_catalog."default" ASC NULLS LAST);

Also, the values that we are seeing is as below:

COL1


COL2


COL3


COL4


COL5


COL6




1


3456


76542


5


ABC


1234




1


3456


76542


5


ABC


1234




2


9872


89765


0


FGT


1234




3


6547


78659


7


JHL


8790

We already defined COL1, COL2, COL3 as primary keys, but still as you see above in the table output, the first 2 rows has exactly same combination for those 3 rows.

Thanks,

Teja.

On Fri, Oct 28, 2022 at 11:41 AM Holger Jakobs <holger(at)jakobs(dot)com> wrote:

Am 28.10.22 um 20:27 schrieb Teja Jakkidi:

> Hi YILDIRIM,

>

> Thanks for your response.

>

> We have a composite primary key on 3columns. We are noticing multiple

> rows with same values in the 3pk columns which should not happen as

> primary constraint is defined on them.

> Also, none of the columns are null.

>

> Regards,

> Teja. J.

>

Unless you don't post your CREATE TABLE command plus some INSERT command

which lead to the described behavior, we won't be able to track the problem.

--

Holger Jakobs, Bergisch Gladbach, Tel. +49-178-9759012