Обсуждение: COPY use in function with variable file name

Hello,

I can't figure out how to make this work, or is not possible?

In a function i would like to read a file.
The file name is determined by a value from a table.
However the COPY statement does not to accept this?
I tried various forms of adding (single)-quotes but no luck.

Anyone any ideas?

Function:
CREATE FUNCTION dnsdhcp_dns_raw()
/* Fill table dns_raw with dns data */
RETURNS integer AS '
DECLARE   r           RECORD;   ntw         TEXT;
BEGIN   /* Do for all domain names */   FOR r IN SELECT domain FROM network       WHERE position(''n'' IN use) > 0 and
ipaddress!= ''127.0.0.0/24''
 
LOOP       ntw := ''/tmp/db.'' || r.domain;       DELETE FROM dns_raw; /* Clear table */
RAISE NOTICE ''Network: %'', ntw;       COPY dns_raw FROM ntw DELIMITERS ''~''; /* Get the data */   END LOOP;   RETURN
0;
END;'
LANGUAGE 'plpgsql';

Result:
id=# select dnsdhcp_dns_raw();
NOTICE:  Network: /tmp/db.test.dummy.com
ERROR:  parser: parse error at or near "$1"

Tables:
CREATE TABLE dns_raw (   data                TEXT
);
                                 Table "network"    Attribute      |  Type   |                      Modifier
--------------------+---------+---------------------------------------------
-------id                 | integer | not null default
nextval('"network_id_seq"'::text)ipaddress          | cidr    | not nulldomain             | text    | not nullemail
         | text    | not nulllocation           | text    | not null default 'l'use                | text    | not null
default's'ttl                | text    | not null default '3h'serial             | integer | not null default 1refresh
         | text    | not null default '3h'retry              | text    | not null default '1h'expire             | text
  | not null default '1w'cachettl           | text    | not null default '1d'lease_time_default | integer | not null
default86400lease_time_minimum | integer | not null default 0lease_time_maximum | integer | not null default
0client_updates    | text    | not null default 'ignore'ddns_update_style  | text    | not null default
'interim'description       | text    |
 

Best regards,
Roelof

On Wed, 2003-01-29 at 08:05, Sondaar Roelof wrote:
> Hello,
> 
> I can't figure out how to make this work, or is not possible?
> 
> In a function i would like to read a file.
> The file name is determined by a value from a table.
> However the COPY statement does not to accept this?
> I tried various forms of adding (single)-quotes but no luck.
> 
> Anyone any ideas?
> 
> Function:
> CREATE FUNCTION dnsdhcp_dns_raw()
> /* Fill table dns_raw with dns data */
> RETURNS integer AS '
> DECLARE
>     r           RECORD;
>     ntw         TEXT;
> BEGIN
>     /* Do for all domain names */
>     FOR r IN SELECT domain FROM network
>         WHERE position(''n'' IN use) > 0 and ipaddress != ''127.0.0.0/24''
> LOOP
>         ntw := ''/tmp/db.'' || r.domain;
>         DELETE FROM dns_raw; /* Clear table */
> RAISE NOTICE ''Network: %'', ntw;
>         COPY dns_raw FROM ntw DELIMITERS ''~''; /* Get the data */

Since ntw has variable content, you need to do an EXECUTE with the
command in a text string:EXECUTE ''COPY dns_raw FROM '' || ntw || '' DELIMITERS ''''='''''';

(I hope that is the right number of quotes!)

>     END LOOP;
>     RETURN 0;
> END;'
> LANGUAGE 'plpgsql';

-- 
Oliver Elphick                                Oliver.Elphick@lfix.co.uk
Isle of Wight, UK                             http://www.lfix.co.uk/oliver
GPG: 1024D/3E1D0C1C: CA12 09E0 E8D5 8870 5839  932A 614D 4C34 3E1D 0C1C
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buthe that doeth the will of God      abideth for ever."             I John 2:15,17