Thread: default timestamp in postresql

Hi,
I need some help to solve a problem regarding transfer the db from
mysql to postresql.
Previously in mysql table field as below , will be add automatic in
database when execute insert statement.

             = submittime timestamp NOT NULL

But in postresql the timestamp cannot insert automatic when execute
insert statement.
How can I solve this problem instead of change the php code?

On Jul 29, 2004, at 4:16 PM, azah azah wrote:

> Previously in mysql table field as below , will be add automatic in
> database when execute insert statement.
>
>              = submittime timestamp NOT NULL

subttime timestamp NOT NULL DEFAULT now()

Michael Glaesemann
grzm myrealbox com

> Previously in mysql table field as below , will be add automatic in
> database when execute insert statement.
>
>              = submittime timestamp NOT NULL
>
> But in postresql the timestamp cannot insert automatic when execute
> insert statement.
> How can I solve this problem instead of change the php code?

Make it:

submittime timestamp not null default current_timestamp

Chris

thanks all, it solve now.

On Thu, 29 Jul 2004 15:30:59 +0800, Christopher Kings-Lynne
<chriskl@familyhealth.com.au> wrote:
> > Previously in mysql table field as below , will be add automatic in
> > database when execute insert statement.
> >
> >              = submittime timestamp NOT NULL
> >
> > But in postresql the timestamp cannot insert automatic when execute
> > insert statement.
> > How can I solve this problem instead of change the php code?
>
> Make it:
>
> submittime timestamp not null default current_timestamp
>
> Chris
>
>

On Thu, 2004-07-29 at 01:16, azah azah wrote:
> Hi,
> I need some help to solve a problem regarding transfer the db from
> mysql to postresql.
> Previously in mysql table field as below , will be add automatic in
> database when execute insert statement.
>
>              = submittime timestamp NOT NULL
>
> But in postresql the timestamp cannot insert automatic when execute
> insert statement.
> How can I solve this problem instead of change the php code?

If you need that field to always be updated whenever the row is changed,
you can use a trigger.

-- FUNCTION --

CREATE FUNCTION modtime () RETURNS opaque AS '
    BEGIN
        new.lm :=''now'';
        RETURN new;
    END;
' LANGUAGE 'plpgsql';

-- TABLE --

CREATE TABLE dtest (
    id int primary key,
    fluff text,
    lm timestamp without time zone
);


--TRIGGER --

CREATE TRIGGER dtest
  BEFORE UPDATE or INSERT ON dtest FOR EACH ROW EXECUTE PROCEDURE
    modtime(lm);

-- SQL TESTS --

INSERT INTO dtest (id, fluff) VALUES (1,'this is a test');
INSERT INTO dtest (id, fluff) VALUES (2,'this is another test');
SELECT * FROM dtest;
  1 | this is a test       | 2003-04-02 10:33:12.577089
  2 | this is another test | 2003-04-02 10:33:18.591148
UPDATE dtest SET id=3 WHERE id=1;
  3 | this is a test | 2003-04-02 10:34:52.219963  [1]
UPDATE dtest SET fluff='now is the time' WHERE id=2;
SELECT * FROM dtest WHERE id=2;
  2 | now is the time | 2003-04-02 10:38:06.259443 [2]
UPDATE dtest SET lm='2003-04-02 08:30:00' WHERE id=3;
SELECT * FROM dtest WHERE id=3;
  3 | this is a test | 2003-04-02 10:36:15.45687 [3]

[1] The timestamp has changed for this record when we changed the id field.
[2] The timestamp also changes for the fluff field.
[3] We tried to set lm, but the trigger on that field in dtest intercepted the change and forced it