Postgres Pro
Downloads
Home   >   mailing lists

Thread: COPY with a variable path

COPY with a variable path

From
Bill Todd
Date:
I want to execute the following COPY command in a stored procedure,
however, I need to pass the path to the file as an input parameter.
Substituting the input parameter for the literal path does not work and
neither does using PREPARE/EXECUTE. How can I pass the file path as a
parameter?

  copy contact.palm_import from 'c:/_junk/palm.csv'
  with delimiter as ','
  null as ''
  csv quote as '"';

Thanks,

Bill

Re: COPY with a variable path

From
Raymond O'Donnell
Date:
On 27/11/2008 20:52, Bill Todd wrote:

> Substituting the input parameter for the literal path does not work and
> neither does using PREPARE/EXECUTE. How can I pass the file path as a
> parameter?

You could write a pl/pgsql function which constructs the query as a
string and then runs it with EXECUTE.

Ray.


------------------------------------------------------------------
Raymond O'Donnell, Director of Music, Galway Cathedral, Ireland
rod@iol.ie
Galway Cathedral Recitals: http://www.galwaycathedral.org/recitals
------------------------------------------------------------------

Re: COPY with a variable path

From
Bill Todd
Date:
Raymond O'Donnell wrote: 
On 27/11/2008 20:52, Bill Todd wrote:
 
Substituting the input parameter for the literal path does not work and
neither does using PREPARE/EXECUTE. How can I pass the file path as a
parameter?   
You could write a pl/pgsql function which constructs the query as a
string and then runs it with EXECUTE.

Ray.


------------------------------------------------------------------
Raymond O'Donnell, Director of Music, Galway Cathedral, Ireland
rod@iol.ie
Galway Cathedral Recitals: http://www.galwaycathedral.org/recitals
------------------------------------------------------------------
According to the PostgreSQL help file EXECUTE is used to execute a prepared statement. I tried that but when I call PREPARE with COPY as the statement I get an error. Are you saying that I can also use EXECUTE as

EXECUTE AStringVariable;

where AStringVariable contains a valid SQL statement? If so, that is the solution.

Bill

Re: COPY with a variable path

From
Bill Todd
Date:
Raymond O'Donnell wrote: 
On 27/11/2008 20:52, Bill Todd wrote:
 
Substituting the input parameter for the literal path does not work and
neither does using PREPARE/EXECUTE. How can I pass the file path as a
parameter?   
You could write a pl/pgsql function which constructs the query as a
string and then runs it with EXECUTE.

Ray.


------------------------------------------------------------------
Raymond O'Donnell, Director of Music, Galway Cathedral, Ireland
rod@iol.ie
Galway Cathedral Recitals: http://www.galwaycathedral.org/recitals
------------------------------------------------------------------
I tried your suggestion and it worked! Thanks.

Bill

Re: COPY with a variable path

From
Raymond O'Donnell
Date:
On 27/11/2008 23:09, Bill Todd wrote:
> Raymond O'Donnell wrote:

>> You could write a pl/pgsql function which constructs the query as a
>> string and then runs it with EXECUTE.

>>
> According to the PostgreSQL help file EXECUTE is used to execute a
> prepared statement. I tried that but when I call PREPARE with COPY as
> the statement I get an error. Are you saying that I can also use EXECUTE as

Sorry, Bill, I wasn't clear enough - I was suggesting writing a pl/pgsql
function something like this (not tested):

  create function do_copy(path text) returns void
  as
  $$
  begin
    execute 'copy your_table from ' || filepath;
    return;
  end;
  $$
  language plpgsql;


EXECUTE in pl/pgsql is different from the version you refer to
above....here it is in the docs:

http://www.postgresql.org/docs/8.3/static/plpgsql-statements.html#PLPGSQL-STATEMENTS-EXECUTING-DYN

Ray.

------------------------------------------------------------------
Raymond O'Donnell, Director of Music, Galway Cathedral, Ireland
rod@iol.ie
Galway Cathedral Recitals: http://www.galwaycathedral.org/recitals
------------------------------------------------------------------