From: Bborie Park <bkpark at ucdavis.edu>
Date: Wed, 18 May 2011 14:18:15 +0000 (+0000)
Subject: ST_SummaryStats returns the sum as part of the summary stats.
X-Git-Tag: 2.0.0alpha1~1618
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=616b91bc702a7cac6f196eb34fcc80aff848dbf4;p=postgis

ST_SummaryStats returns the sum as part of the summary stats.
_ST_SummaryStats(rastertable, rastercolumn) function changed to make use of the sum and compute a straight mean (sum / count) rather than computing a weighted mean.


git-svn-id: http://svn.osgeo.org/postgis/trunk@7193 b70326c6-7e19-0410-871a-916f4a2858ee
---

diff --git a/raster/rt_core/rt_api.c b/raster/rt_core/rt_api.c
index 035afe507..62be5de40 100644
--- a/raster/rt_core/rt_api.c
+++ b/raster/rt_core/rt_api.c
@@ -1489,6 +1489,7 @@ struct rt_bandstats_t {
 
 	double min;
 	double max;
+	double sum;
 	double mean;
 	double stddev;
 
@@ -1584,6 +1585,7 @@ rt_band_get_summary_stats(rt_band band, int hasnodata, double sample,
 			stats->sample = 1;
 			stats->count = band->width * band->height;
 			stats->min = stats->max = nodata;
+			stats->sum = stats->count * nodata;
 			stats->mean = nodata;
 			stats->stddev = 0;
 			stats->values = NULL;
@@ -1696,6 +1698,7 @@ rt_band_get_summary_stats(rt_band band, int hasnodata, double sample,
 						stats->sample = sample;
 						stats->count = 0;
 
+						stats->sum = 0;
 						stats->mean = 0;
 						stats->stddev = -1;
 						stats->min = stats->max = value;
@@ -1731,6 +1734,7 @@ rt_band_get_summary_stats(rt_band band, int hasnodata, double sample,
 		}
 
 		stats->count = k;
+		stats->sum = sum;
 		stats->mean = sum / k;
 
 		/* standard deviation */
diff --git a/raster/rt_pg/rt_pg.c b/raster/rt_pg/rt_pg.c
index bb42addd3..d6d94238c 100644
--- a/raster/rt_pg/rt_pg.c
+++ b/raster/rt_pg/rt_pg.c
@@ -2922,6 +2922,7 @@ struct rt_bandstats_t {
 
 	double min;
 	double max;
+	double sum;
 	double mean;
 	double stddev;
 
@@ -2935,188 +2936,158 @@ struct rt_bandstats_t {
 PG_FUNCTION_INFO_V1(RASTER_summaryStats);
 Datum RASTER_summaryStats(PG_FUNCTION_ARGS)
 {
-	FuncCallContext *funcctx;
+	rt_pgraster *pgraster = (rt_pgraster *) PG_DETOAST_DATUM(PG_GETARG_DATUM(0));
+	rt_raster raster = NULL;
+	rt_band band = NULL;
+	int32_t bandindex = 0;
+	bool hasnodata = TRUE;
+	int num_bands = 0;
+	double sample = 0;
+	rt_bandstats stats = NULL;
+
 	TupleDesc tupdesc;
 	AttInMetadata *attinmeta;
 
-	rt_bandstats stats;
-	rt_bandstats stats2;
-	int call_cntr;
-	int max_calls;
-
-	/* first call of function */
-	if (SRF_IS_FIRSTCALL()) {
-		MemoryContext oldcontext;
+	char **values;
+	HeapTuple tuple;
+	Datum result;
 
-		rt_pgraster *pgraster = (rt_pgraster *) PG_DETOAST_DATUM(PG_GETARG_DATUM(0));
-		rt_raster raster = NULL;
-		rt_band band = NULL;
-		int32_t bandindex = 0;
-		bool hasnodata = TRUE;
-		int num_bands = 0;
-		double sample = 0;
-
-		/* create a function context for cross-call persistence */
-		funcctx = SRF_FIRSTCALL_INIT();
+	raster = rt_raster_deserialize(pgraster);
+	if (!raster) {
+		elog(ERROR, "RASTER_summaryStats: Could not deserialize raster");
+		PG_RETURN_NULL();
+	}
 
-		/* switch to memory context appropriate for multiple function calls */
-		oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
+	/* band index is 1-based */
+	bandindex = PG_GETARG_INT32(1);
+	num_bands = rt_raster_get_num_bands(raster);
+	if (bandindex < 1 || bandindex > num_bands) {
+		elog(NOTICE, "Invalid band index (must use 1-based). Returning NULL");
+		rt_raster_destroy(raster);
+		PG_RETURN_NULL();
+	}
+	assert(0 <= (bandindex - 1));
 
-		raster = rt_raster_deserialize(pgraster);
-		if (!raster) {
-			elog(ERROR, "RASTER_summaryStats: Could not deserialize raster");
-			PG_RETURN_NULL();
-		}
+	/* hasnodata flag */
+	if (!PG_ARGISNULL(2))
+		hasnodata = PG_GETARG_BOOL(2);
 
-		/* band index is 1-based */
-		bandindex = PG_GETARG_INT32(1);
-		num_bands = rt_raster_get_num_bands(raster);
-		if (bandindex < 1 || bandindex > num_bands) {
-			elog(NOTICE, "Invalid band index (must use 1-based). Returning NULL");
+	/* sample % */
+	if (!PG_ARGISNULL(3)) {
+		sample = PG_GETARG_FLOAT8(3);
+		if (sample < 0 || sample > 1) {
+			elog(NOTICE, "Invalid sample percentage (must be between 0 and 1). Returning NULL");
 			rt_raster_destroy(raster);
 			PG_RETURN_NULL();
 		}
-		assert(0 <= (bandindex - 1));
-
-		/* hasnodata flag */
-		if (!PG_ARGISNULL(2))
-			hasnodata = PG_GETARG_BOOL(2);
-
-		/* sample % */
-		if (!PG_ARGISNULL(3)) {
-			sample = PG_GETARG_FLOAT8(3);
-			if (sample < 0 || sample > 1) {
-				elog(NOTICE, "Invalid sample percentage (must be between 0 and 1). Returning NULL");
-				rt_raster_destroy(raster);
-				PG_RETURN_NULL();
-			}
-			else if (sample == 0)
-				sample = 1;
-		}
-		else
+		else if (sample == 0)
 			sample = 1;
+	}
+	else
+		sample = 1;
 
-		/* get band */
-		band = rt_raster_get_band(raster, bandindex - 1);
-		if (!band) {
-			elog(NOTICE, "Could not find raster band of index %d. Returning NULL", bandindex);
-			rt_raster_destroy(raster);
-			PG_RETURN_NULL();
-		}
-
-		/* we don't need the raw values, hence the zero parameter */
-		stats = rt_band_get_summary_stats(band, (int) hasnodata, sample, 0);
-		rt_band_destroy(band);
+	/* get band */
+	band = rt_raster_get_band(raster, bandindex - 1);
+	if (!band) {
+		elog(NOTICE, "Could not find raster band of index %d. Returning NULL", bandindex);
 		rt_raster_destroy(raster);
-		if (NULL == stats) {
-			elog(NOTICE, "Could not retrieve summary statistics of band of index %d. Returning NULL", bandindex);
-			PG_RETURN_NULL();
-		}
-
-		/* store needed data */
-		funcctx->user_fctx = stats;
-
-		/* total number of tuples to return */
-		funcctx->max_calls = 1;
-
-		/* Build a tuple descriptor for our result type */
-		if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE) {
-			ereport(ERROR, (
-				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				errmsg(
-					"function returning record called in context "
-					"that cannot accept type record"
-				)
-			));
-		}
-
-		/*
-		 * generate attribute metadata needed later to produce tuples from raw
-		 * C strings
-		 */
-		attinmeta = TupleDescGetAttInMetadata(tupdesc);
-		funcctx->attinmeta = attinmeta;
-		MemoryContextSwitchTo(oldcontext);
-
+		PG_RETURN_NULL();
 	}
 
-  /* stuff done on every call of the function */
-  funcctx = SRF_PERCALL_SETUP();
-
-	call_cntr = funcctx->call_cntr;
-	max_calls = funcctx->max_calls;
-	attinmeta = funcctx->attinmeta;
-	stats2 = funcctx->user_fctx;
-
-	/* do when there is more left to send */
-	if (call_cntr < max_calls) {
-		char **values;
-		HeapTuple tuple;
-		Datum result;
-
-		POSTGIS_RT_DEBUGF(3, "tuple #%d", call_cntr);
-
-		/*
-		 * Prepare a values array for building the returned tuple.
-		 * This should be an array of C strings which will
-		 * be processed later by the type input functions.
-		 */
-		values = (char **) palloc(5 * sizeof(char *));
-
-		values[0] = (char *) palloc(sizeof(char) * (MAX_INT_CHARLEN + 1));
-		values[1] = (char *) palloc(sizeof(char) * (MAX_DBL_CHARLEN + 1));
-		values[2] = (char *) palloc(sizeof(char) * (MAX_DBL_CHARLEN + 1));
-		values[3] = (char *) palloc(sizeof(char) * (MAX_DBL_CHARLEN + 1));
-		values[4] = (char *) palloc(sizeof(char) * (MAX_DBL_CHARLEN + 1));
-
-		snprintf(
-			values[0],
-			sizeof(char) * (MAX_INT_CHARLEN + 1),
-			"%d",
-			stats2[call_cntr].count
-		);
-		snprintf(
-			values[1],
-			sizeof(char) * (MAX_DBL_CHARLEN + 1),
-			"%f",
-			stats2[call_cntr].mean
-		);
-		snprintf(
-			values[2],
-			sizeof(char) * (MAX_DBL_CHARLEN + 1),
-			"%f",
-			stats2[call_cntr].stddev
-		);
-		snprintf(
-			values[3],
-			sizeof(char) * (MAX_DBL_CHARLEN + 1),
-			"%f",
-			stats2[call_cntr].min
-		);
-		snprintf(
-			values[4],
-			sizeof(char) * (MAX_DBL_CHARLEN + 1),
-			"%f",
-			stats2[call_cntr].max
-		);
-
-		/* build a tuple */
-		tuple = BuildTupleFromCStrings(attinmeta, values);
+	/* we don't need the raw values, hence the zero parameter */
+	stats = rt_band_get_summary_stats(band, (int) hasnodata, sample, 0);
+	rt_band_destroy(band);
+	rt_raster_destroy(raster);
+	if (NULL == stats) {
+		elog(NOTICE, "Could not retrieve summary statistics of band of index %d. Returning NULL", bandindex);
+		PG_RETURN_NULL();
+	}
 
-		/* make the tuple into a datum */
-		result = HeapTupleGetDatum(tuple);
+	/* Build a tuple descriptor for our result type */
+	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE) {
+		ereport(ERROR, (
+			errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+			errmsg(
+				"function returning record called in context "
+				"that cannot accept type record"
+			)
+		));
+	}
 
-		/* clean up */
-		pfree(values[1]);
-		pfree(values[0]);
-		pfree(values);
+	/*
+	 * generate attribute metadata needed later to produce tuples from raw
+	 * C strings
+	 */
+	attinmeta = TupleDescGetAttInMetadata(tupdesc);
 
-		SRF_RETURN_NEXT(funcctx, result);
-	}
-	else {
-		pfree(stats2);
-		SRF_RETURN_DONE(funcctx);
-	}
+	/*
+	 * Prepare a values array for building the returned tuple.
+	 * This should be an array of C strings which will
+	 * be processed later by the type input functions.
+	 */
+	values = (char **) palloc(6 * sizeof(char *));
+
+	values[0] = (char *) palloc(sizeof(char) * (MAX_INT_CHARLEN + 1));
+	values[1] = (char *) palloc(sizeof(char) * (MAX_DBL_CHARLEN + 1));
+	values[2] = (char *) palloc(sizeof(char) * (MAX_DBL_CHARLEN + 1));
+	values[3] = (char *) palloc(sizeof(char) * (MAX_DBL_CHARLEN + 1));
+	values[4] = (char *) palloc(sizeof(char) * (MAX_DBL_CHARLEN + 1));
+	values[5] = (char *) palloc(sizeof(char) * (MAX_DBL_CHARLEN + 1));
+
+	snprintf(
+		values[0],
+		sizeof(char) * (MAX_INT_CHARLEN + 1),
+		"%d",
+		stats->count
+	);
+	snprintf(
+		values[1],
+		sizeof(char) * (MAX_DBL_CHARLEN + 1),
+		"%f",
+		stats->sum
+	);
+	snprintf(
+		values[2],
+		sizeof(char) * (MAX_DBL_CHARLEN + 1),
+		"%f",
+		stats->mean
+	);
+	snprintf(
+		values[3],
+		sizeof(char) * (MAX_DBL_CHARLEN + 1),
+		"%f",
+		stats->stddev
+	);
+	snprintf(
+		values[4],
+		sizeof(char) * (MAX_DBL_CHARLEN + 1),
+		"%f",
+		stats->min
+	);
+	snprintf(
+		values[5],
+		sizeof(char) * (MAX_DBL_CHARLEN + 1),
+		"%f",
+		stats->max
+	);
+
+	/* build a tuple */
+	tuple = BuildTupleFromCStrings(attinmeta, values);
+
+	/* make the tuple into a datum */
+	result = HeapTupleGetDatum(tuple);
+
+	/* clean up */
+	pfree(values[5]);
+	pfree(values[4]);
+	pfree(values[3]);
+	pfree(values[2]);
+	pfree(values[1]);
+	pfree(values[0]);
+	pfree(values);
+	pfree(stats);
+
+	PG_RETURN_DATUM(result);
 }
 
 /* get histogram */
diff --git a/raster/rt_pg/rtpostgis.sql.in.c b/raster/rt_pg/rtpostgis.sql.in.c
index 7d91e0a25..c5a5bb2ad 100644
--- a/raster/rt_pg/rtpostgis.sql.in.c
+++ b/raster/rt_pg/rtpostgis.sql.in.c
@@ -263,6 +263,7 @@ CREATE OR REPLACE FUNCTION st_band(rast raster)
 -----------------------------------------------------------------------
 CREATE TYPE summarystats AS (
 	count integer,
+	sum double precision,
 	mean double precision,
 	stddev double precision,
 	min double precision,
@@ -276,47 +277,47 @@ CREATE OR REPLACE FUNCTION _st_summarystats(rast raster, nband int, hasnodata bo
 
 CREATE OR REPLACE FUNCTION st_summarystats(rast raster, nband int, hasnodata boolean)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, 1) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, 1) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_summarystats(rast raster, nband int)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, $2, TRUE, 1) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, $2, TRUE, 1) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_summarystats(rast raster, hasnodata boolean)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, 1, $2, 1) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, 1, $2, 1) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_summarystats(rast raster)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, 1, TRUE, 1) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, 1, TRUE, 1) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_approxsummarystats(rast raster, nband int, hasnodata boolean, sample_percent double precision)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, $4) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, $4) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_approxsummarystats(rast raster, nband int, sample_percent double precision)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, $2, TRUE, $3) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, $2, TRUE, $3) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_approxsummarystats(rast raster, hasnodata boolean, sample_percent double precision)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, 1, $2, $3) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, 1, $2, $3) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_approxsummarystats(rast raster, sample_percent double precision)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, 1, TRUE, $2) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, 1, TRUE, $2) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_approxsummarystats(rast raster)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, 1, TRUE, 0.1) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, 1, TRUE, 0.1) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION _st_summarystats(rastertable text, rastercolumn text, nband integer, hasnodata boolean, sample_percent double precision)
@@ -331,7 +332,8 @@ CREATE OR REPLACE FUNCTION _st_summarystats(rastertable text, rastercolumn text,
 		stats summarystats;
 		rtn summarystats;
 
-		mean double precision;
+		avg double precision;
+		wavg double precision;
 		tmp double precision;
 	BEGIN		
 		-- nband
@@ -364,19 +366,21 @@ CREATE OR REPLACE FUNCTION _st_summarystats(rastertable text, rastercolumn text,
 				RETURN NULL;
 		END;
 
-		mean := 0;
+		avg := 0;
+		wavg := 0;
 		tmp := 0;
 		LOOP
 			FETCH curs INTO rast;
 			EXIT WHEN NOT FOUND;
 
-			SELECT * FROM _st_summarystats(rast, nband, hasnodata, sample_percent) INTO stats;
+			SELECT count, sum, mean, stddev, min, max FROM _st_summarystats(rast, nband, hasnodata, sample_percent) INTO stats;
 			IF stats IS NULL OR stats.count < 1 THEN
 				CONTINUE;
 			END IF;
 			--RAISE NOTICE 'stats = %', stats;
 
-			mean := mean + (stats.count * stats.mean); -- not the mean
+			avg := avg + stats.sum; -- not the mean
+			wavg := wavg + (stats.count * stats.mean); -- not the mean
 			-- sum of "sum of squares"
 			IF sample_percent > 0 AND sample_percent < 1 THEN
 				tmp := tmp + (power(stats.stddev, 2) * (stats.count - 1));
@@ -401,9 +405,12 @@ CREATE OR REPLACE FUNCTION _st_summarystats(rastertable text, rastercolumn text,
 
 		CLOSE curs;
 
-		-- weighted mean and cumulative stddev
+		-- mean and cumulative stddev
 		IF rtn.count IS NOT NULL AND rtn.count > 0 THEN
-			rtn.mean := mean / rtn.count;
+			rtn.mean := avg / rtn.count;
+			wavg := wavg / rtn.count;
+			--RAISE NOTICE 'straight avg = %', avg;
+			--RAISE NOTICE 'weighted avg = %', wavg;
 			rtn.stddev := sqrt(tmp / rtn.count);
 		END IF;
 
@@ -413,42 +420,42 @@ CREATE OR REPLACE FUNCTION _st_summarystats(rastertable text, rastercolumn text,
 
 CREATE OR REPLACE FUNCTION st_summarystats(rastertable text, rastercolumn text, nband integer, hasnodata boolean)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, $4, 1) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, $4, 1) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_summarystats(rastertable text, rastercolumn text, nband integer)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, TRUE, 1) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, TRUE, 1) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_summarystats(rastertable text, rastercolumn text)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, $2, 1, TRUE, 1) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, $2, 1, TRUE, 1) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_approxsummarystats(rastertable text, rastercolumn text, nband integer, hasnodata boolean, sample_percent double precision)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, $4, $5) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, $4, $5) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_approxsummarystats(rastertable text, rastercolumn text, nband integer, sample_percent double precision)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, TRUE, $4) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, TRUE, $4) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_approxsummarystats(rastertable text, rastercolumn text, nband integer)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, TRUE, 0.1) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, $2, $3, TRUE, 0.1) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_approxsummarystats(rastertable text, rastercolumn text, sample_percent double precision)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, $2, 1, TRUE, $3) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, $2, 1, TRUE, $3) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 CREATE OR REPLACE FUNCTION st_approxsummarystats(rastertable text, rastercolumn text)
 	RETURNS summarystats
-	AS $$ SELECT count, mean, stddev, min, max FROM _st_summarystats($1, $2, 1, TRUE, 0.1) $$
+	AS $$ SELECT count, sum, mean, stddev, min, max FROM _st_summarystats($1, $2, 1, TRUE, 0.1) $$
 	LANGUAGE 'SQL' IMMUTABLE STRICT;
 
 -----------------------------------------------------------------------
diff --git a/raster/test/core/testapi.c b/raster/test/core/testapi.c
index 915c56177..0d9319e6d 100644
--- a/raster/test/core/testapi.c
+++ b/raster/test/core/testapi.c
@@ -993,6 +993,7 @@ struct rt_bandstats_t {
 
 	double min;
 	double max;
+	double sum;
 	double mean;
 	double stddev;
 
diff --git a/raster/test/regress/rt_summarystats_expected b/raster/test/regress/rt_summarystats_expected
index 98c347e5e..d366dc47d 100644
--- a/raster/test/regress/rt_summarystats_expected
+++ b/raster/test/regress/rt_summarystats_expected
@@ -1,12 +1,12 @@
-2|-3.429205|6.570795|-10|3.14159
-(2,-3.429205,6.570795,-10,3.14159)
+2|-6.85841|-3.429205|6.570795|-10|3.14159
+(2,-6.85841,-3.429205,6.570795,-10,3.14159)
 2
 100
 -3.429205|6.570795
 -0.068584|1.045941
 BEGIN
-20|-3.429205|6.570795|-10|3.14159
-1000|-0.068584|1.045941|-10|3.14159
-20|-3.429205|6.570795|-10|3.14159
-20|-3.429205|6.570795|-10|3.14159
+20|-6.85841|-3.429205|6.570795|-10|3.14159
+1000|-6.85841|-0.0685841|1.045941|-10|3.14159
+20|-6.85841|-3.429205|6.570795|-10|3.14159
+20|-6.85841|-3.429205|6.570795|-10|3.14159
 COMMIT
diff --git a/raster/test/regress/run_test.in b/raster/test/regress/run_test.in
index 8afe79aef..07799798e 100644
--- a/raster/test/regress/run_test.in
+++ b/raster/test/regress/run_test.in
@@ -113,6 +113,7 @@ run_simple_test ()
 	${PSQL} -tA < "${_sql}" ${DB} > ${TMPFILE} 2>&1
 	cat ${TMPFILE} \
 		| grep -v "^$" \
+		| grep -v "^SELECT" \
 		| grep -v "^INSERT" \
 		| grep -v "^DELETE" \
 		| grep -v "^CONTEXT" \