Re: Exporting a PDF from a bytea column

[CS DBA <cs_dba@xxxxxxxxxxxxxxxxxxx>]

On 02/18/2016 07:29 PM, David G. Johnston wrote:

On Thursday, February 18, 2016, John R Pierce <pierce@xxxxxxxxxxxx> wrote:

On 2/18/2016 4:44 PM, CS DBA wrote:

The system stores PDF's as large objects
in bytea columns.

Large Objects aka LO's and bytea columns are two completely different things.

I'll assume the "column" is the most relevant term here because the above is true.

 

Can anyone send me an example of
exporting from a bytea column to a PDF file?

I don't think you can get from a bytea field to a file without some coding, as SQL scripting doesn't handle binary blobs very well.

http://www.postgresql.org/message-id/AANLkTi=2dARHQPRGTXmCx0aus9maHQ2SfxxbvihtuzDv@xxxxxxxxxxxxxx

Short answer, to avoid the binary blob problem, is to encode the binary data, export it, then decode it.

This can be done is psql.  If your client can handle binary directly (e.g, JDBC/Java) you can use that language's facilities to perform the binary transfer directly thus bypassing the need to transcode.

Can it be done from a Linux shell script?  Any examples? Seems to be little info on this in my googling?

David J,