[gdal-dev] Questions about SQL cursors in GDAL driver

[Jorge Arévalo]

Hello,

Context: GDAL WKTRaster Driver. When creating Dataset, I declare a
cursor to read all the rows (tiles) of a table with a raster column
(DECLARE cursor CURSOR FOR SELECT * FROM TABLE). The RasterBand should
read one of the rows' band

Question 1: The cursor is created during the Dataset creation, and
stored in it. Should I start a transaction before? If yes, when should
I close the cursor and end the transaction? When calling to Dataset's
destructor?
Question 2: What approach is better?
     a) The Dataset fetchs all the rows (tiles) of the table just
after declaring the cursor, and the RasterBand moves over the
resultset using PQgetvalue and read one band of the read raster
     b) The Dataset declare the cursor and the RasterBand fetchs the
row that needs to read one of its bands

Thanks in advance.

Best regards
Jorge