v.rast.stats: speed-up - use db transactions

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@58707 15284696-431f-4ddb-bdfa-cd5b030d7da7

scripts/v.rast.stats/v.rast.stats.py

@@ -224,6 +224,7 @@ def main():
                       zones = rastertmp, percentile = percentile, sep = ';')
 
     first_line = 1
+    f.write("BEGIN TRANSACTION\n")
     for line in p.stdout:
 	if first_line:
 	    first_line = 0
@@ -250,6 +251,7 @@ def main():
 		i += 1
 
 	f.write(" WHERE %s=%s;\n" % (fi['key'], vars[0]))
+    f.write("COMMIT\n")
 
     p.wait()
     f.close()