Bryce Nesbitt wrote: > Craig Ringer wrote: >> Yes - but you are *not* presenting a Latin-1 character. You're >> presenting four Latin-1 characters: >> >> '\', '3', '7', '5' > Well, then I have a different question. If I can view a bytea column as > so: > >> select object from context_objects where context_key=100041; > object > ----------------------------- > \005\007\021\007Article\003 > (1 row) > > How can I modify the data and put it back into the column?
Oh: you might also find the encode(...) function useful. From : http://www.postgresql.org/docs/current/static/functions-string.html encode(data bytea, type text) returns text Encode binary data to different representation. Supported types are: base64, hex, escape. Escape merely outputs null bytes as \000 and doubles backslashes. so rather than struggling through Pg's octal-escaped strings you can ask for them in hex or base64 form, eg: craig=> \d context_objects Table "public.context_objects" Column | Type | Modifiers --------+---------+-------------------------------------------------------------- id | integer | not null default nextval('context_objects_id_seq'::regclass) object | bytea | not null Indexes: "context_objects_pkey" PRIMARY KEY, btree (id) craig=> select * from context_objects; id | object ----+----------------------------- 1 | \005\007\021\007Article\003 2 | test\375 (2 rows) craig=> SELECT encode( object, 'hex' ) FROM context_objects; encode -------------------------- 0507110741727469636c6503 74657374fd (2 rows) craig=> SELECT encode( object, 'base64' ) FROM context_objects; encode ------------------ BQcRB0FydGljbGUD dGVzdP0= (2 rows) Both the hex-string and base64 forms are trivial to convert to and from a byte string in Perl. You can use the matching 'decode' function when updating / inserting data, eg: UPDATE context_objects SET object = decode('BQcRB0FydGljbGUD', 'base64') WHERE id = 2; -- Craig Ringer -- Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-sql
