MIME-Version: 1.0
From: Stephen Lagree <stephen.lagree@gmail.com>
Date: Tue, 31 Mar 2020 15:27:05 -0700
Message-ID: 
 <CADkZaxXqU+c6_GnW_L0SOgc63iYHomm0RVSpb_+Kww5scVyA4w@mail.gmail.com>
Subject: Inserting default values into execute_values
To: psycopg@postgresql.org
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Hello,

I am trying to insert into a table to generate sequential ids.  Is there a
way to do this repeatedly using execute_values if there is only one column
and it is auto incremented?
It seems the execute_values requires at least one non-default value.

I am trying to do this:
    query = "INSERT INTO MYTABLE (id) VALUES (DEFAULT) RETURNING id;"
    execute_values(cursor, query, args_list, template=None, page_size=100,
fetch=True)

If I don't use a %s argument and just put dummy values in the arglist, I
get error
E           ValueError: the query doesn't contain any '%s' placeholder
I understand why this doesn't work because it can't extract the placeholder
and replicate values there.

If I change DEFAULT to %s and try to use blank tuples I get this
E           psycopg2.errors.SyntaxError: syntax error at or near ")"
E           LINE 1: INSERT INTO MYTABLE (id) VALUES (),(),() RETURNING id;

If I use "DEFAULT" as a string it tries to insert a string into an int
column, not use the DEFAULT value.  Is there a way to insert the default
value here?  I don't see anything like this in the documentation.

My table looks like this:
"CREATE TABLE MYTABLE (id SERIAL PRIMARY KEY)"

Thanks,
Steve

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<div dir=3D"ltr">Hello,<div><br></div><div>I am trying to insert into a tab=
le to generate sequential ids.=C2=A0 Is there a way to do this repeatedly u=
sing execute_values if there is only one column and it is auto incremented?=
=C2=A0=C2=A0</div><div>It seems the execute_values requires at least one no=
n-default value.</div><div><br></div><div>I am trying to do this:</div><div=
>=C2=A0 =C2=A0 query =3D &quot;INSERT INTO MYTABLE (id) VALUES (DEFAULT) RE=
TURNING id;&quot;<br></div><div>=C2=A0 =C2=A0 execute_values(cursor, query,=
 args_list, template=3DNone, page_size=3D100, fetch=3DTrue)</div><div><br><=
/div><div>If I don&#39;t use a %s argument and just put dummy values in the=
 arglist, I get error</div><div>E =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 ValueE=
rror: the query doesn&#39;t contain any &#39;%s&#39; placeholder<br></div><=
div>I understand why this doesn&#39;t work because it can&#39;t extract the=
 placeholder and replicate values there.</div><div><br></div><div>If I chan=
ge DEFAULT to %s and try to use blank tuples I get this<br></div><div>E =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 psycopg2.errors.SyntaxError: syntax error a=
t or near &quot;)&quot;<br>E =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 LINE 1: INS=
ERT INTO MYTABLE (id) VALUES (),(),() RETURNING id;<br></div><div><br></div=
><div>If I use &quot;DEFAULT&quot; as a string it tries to insert a string =
into an int column, not use the DEFAULT value.=C2=A0 Is there a way to inse=
rt the default value here?=C2=A0 I don&#39;t see anything like this in the =
documentation.</div><div><br></div><div>My table looks like this:</div><div=
>&quot;CREATE TABLE MYTABLE (id SERIAL PRIMARY KEY)&quot;<br></div><div><br=
></div><div>Thanks,</div><div>Steve</div></div>

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