Thread: binary format of array stored as text
I have an old table with a column specified as integer[]. The data within this column was stored as text ala {1,2,3,…} yada yada. I have an application where I am reading all the columns from a row in this table in binary format. Does anybody know how I can recast/reshape this binary data back into an array of integers?
The array in text format is:
{0,3,3,18,19,19,35,35}
The array in binary format is:
0000 0001 0000 0000 0000 0017 0000 0008
0000 0001 0000 0004 0000 0000 0000 0004
0000 0003 0000 0004 0000 0003 0000 0004
0000 0012 0000 0004 0000 0013 0000 0004
0000 0013 0000 0004 0000 0023 0000 0004
0000 0023
I can make some assumptions to interpet “0000 0004 0000 0023” as a 32-bit length followed by length bytes (length = 4, data = 0x23 = 35), but I have no clue how to interpret the leading 20 bytes of this data.
I appreciate any help I can get.
Thanks,
Dave Huber
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On Wed, Sep 2, 2009 at 3:50 PM, Dave
Huber<DHuber@letourneautechnologies.com> wrote:
> I have an old table with a column specified as integer[]. The data within
> this column was stored as text ala {1,2,3,…} yada yada. I have an
> application where I am reading all the columns from a row in this table in
> binary format. Does anybody know how I can recast/reshape this binary data
> back into an array of integers?
check out our libpqtypes library:
http://libpqtypes.esilo.com/
It pulls all data as binary and allows you to access array elements,
and you can write data the same way. PostgreSQL binary formats are
more complicated than you think: there is dimension information, etc.
in there. (that said, sending int[] as binary is much faster).
merlin