[PGPRO-5435] Added functions that output top(n) execution time queries and top(n) cardinality error queries without using aqo.

Makefile

@@ -21,7 +21,8 @@ REGRESS =	aqo_disabled \
 			gucs \
 			forced_stat_collection \
 			unsupported \
-			clean_aqo_data
+			clean_aqo_data \
+			top_queries
 
 fdw_srcdir = $(top_srcdir)/contrib/postgres_fdw
 PG_CPPFLAGS += -I$(libpq_srcdir) -I$(fdw_srcdir)

aqo--1.2--1.3.sql

@@ -7,11 +7,10 @@ DECLARE
     aqo_query_texts_row aqo_query_texts%ROWTYPE;
     aqo_query_stat_row aqo_query_stat%ROWTYPE;
     oid_var oid;
-    fspace_hash_var numeric;
+    fspace_hash_var int;
     delete_row boolean DEFAULT false;
 BEGIN
     RAISE NOTICE 'Cleaning aqo_data records';
-
     FOR aqo_data_row IN
         SELECT * FROM aqo_data
     LOOP
@@ -25,15 +24,13 @@ BEGIN
                 END IF;
             END LOOP;
         END IF;
-
         FOR aqo_queries_row IN
             SELECT * FROM aqo_queries
         LOOP
             IF (delete_row = true AND
                 fspace_hash_var <> 0 AND
                 fspace_hash_var = aqo_queries_row.fspace_hash AND
                 aqo_queries_row.fspace_hash = aqo_queries_row.query_hash) THEN
-
                 DELETE FROM aqo_data WHERE aqo_data = aqo_data_row;
                 DELETE FROM aqo_queries WHERE aqo_queries = aqo_queries_row;
                 FOR aqo_query_texts_row IN
@@ -52,4 +49,32 @@ BEGIN
         END LOOP;
     END LOOP;
 END;
+$$ LANGUAGE plpgsql;
+
+CREATE OR REPLACE FUNCTION public.top_execution_time_queries(n int)
+    RETURNS TABLE(num bigint,
+                  class int,
+                  execution_time double precision[]
+                  )
+        AS $$
+BEGIN
+    RAISE NOTICE 'Top % execution time classes of queries', n;
+    RETURN QUERY SELECT row_number() OVER(ORDER BY execution_time_without_aqo DESC) num, aqo_query_stat.query_hash, execution_time_without_aqo
+        FROM aqo_query_stat RIGHT OUTER JOIN aqo_queries ON aqo_queries.fspace_hash = aqo_query_stat.query_hash WHERE aqo_query_stat.query_hash <> 0
+            GROUP BY aqo_query_stat.query_hash ORDER BY execution_time_without_aqo DESC LIMIT n;
+END;
+$$ LANGUAGE plpgsql;
+
+CREATE OR REPLACE FUNCTION public.top_cardinality_error_queries(n int)
+    RETURNS TABLE(num bigint,
+                  class int,
+                  cardinality_error double precision[]
+                  )
+        AS $$
+BEGIN
+    RAISE NOTICE 'Top % cardinality error classes of queries', n;
+    RETURN QUERY SELECT row_number() OVER(ORDER BY cardinality_error_without_aqo DESC) num, aqo_query_stat.query_hash, cardinality_error_without_aqo
+        FROM aqo_query_stat RIGHT OUTER JOIN aqo_queries ON aqo_queries.fspace_hash = aqo_query_stat.query_hash WHERE aqo_query_stat.query_hash <> 0
+            GROUP BY aqo_query_stat.query_hash ORDER BY cardinality_error_without_aqo DESC LIMIT n;
+END;
 $$ LANGUAGE plpgsql;

expected/top_queries.out

@@ -0,0 +1,52 @@
+CREATE EXTENSION aqo;
+ERROR:  extension "aqo" already exists
+SET aqo.mode = 'disabled';
+SET aqo.force_collect_stat = 'on';
+--
+-- num of generate_series(1,1000000) query should be the first
+--
+SELECT count(*) FROM generate_series(1,1000000);
+  count  
+---------
+ 1000000
+(1 row)
+
+SELECT num FROM top_execution_time_queries(10) WHERE
+    class = (SELECT fspace_hash FROM aqo_queries WHERE
+        aqo_queries.query_hash = (SELECT aqo_query_texts.query_hash FROM aqo_query_texts
+            WHERE query_text = 'SELECT count(*) FROM generate_series(1,1000000);'));
+NOTICE:  Top 10 execution time classes of queries
+ num 
+-----
+   1
+(1 row)
+
+--
+-- num of query uses t2 should be bigger than num of query uses t1 and be the fisrt
+--
+CREATE TABLE t1 AS SELECT mod(gs,10) AS x, mod(gs+1,10) AS y
+	FROM generate_series(1,1000) AS gs;
+CREATE TABLE t2 AS SELECT mod(gs,10) AS x, mod(gs+1,10) AS y
+	FROM generate_series(1,100000) AS gs;
+SELECT count(*) FROM (SELECT x, y FROM t1 GROUP BY GROUPING SETS ((x,y), (x), (y), ())) AS q1;
+ count 
+-------
+    31
+(1 row)
+
+SELECT count(*) FROM (SELECT x, y FROM t2 GROUP BY GROUPING SETS ((x,y), (x), (y), ())) AS q1;
+ count 
+-------
+    31
+(1 row)
+
+SELECT num FROM top_cardinality_error_queries(10) WHERE
+    class = (SELECT fspace_hash FROM aqo_queries WHERE
+        aqo_queries.query_hash = (SELECT aqo_query_texts.query_hash FROM aqo_query_texts
+            WHERE query_text = 'SELECT count(*) FROM (SELECT x, y FROM t2 GROUP BY GROUPING SETS ((x,y), (x), (y), ())) AS q1;'));
+NOTICE:  Top 10 cardinality error classes of queries
+ num 
+-----
+   1
+(1 row)
+

sql/top_queries.sql

@@ -0,0 +1,27 @@
+CREATE EXTENSION aqo;
+SET aqo.mode = 'disabled';
+SET aqo.force_collect_stat = 'on';
+
+--
+-- num of generate_series(1,1000000) query should be the first
+--
+SELECT count(*) FROM generate_series(1,1000000);
+SELECT num FROM top_execution_time_queries(10) WHERE
+    class = (SELECT fspace_hash FROM aqo_queries WHERE
+        aqo_queries.query_hash = (SELECT aqo_query_texts.query_hash FROM aqo_query_texts
+            WHERE query_text = 'SELECT count(*) FROM generate_series(1,1000000);'));
+
+--
+-- num of query uses t2 should be bigger than num of query uses t1 and be the fisrt
+--
+CREATE TABLE t1 AS SELECT mod(gs,10) AS x, mod(gs+1,10) AS y
+	FROM generate_series(1,1000) AS gs;
+CREATE TABLE t2 AS SELECT mod(gs,10) AS x, mod(gs+1,10) AS y
+	FROM generate_series(1,100000) AS gs;
+SELECT count(*) FROM (SELECT x, y FROM t1 GROUP BY GROUPING SETS ((x,y), (x), (y), ())) AS q1;
+SELECT count(*) FROM (SELECT x, y FROM t2 GROUP BY GROUPING SETS ((x,y), (x), (y), ())) AS q1;
+
+SELECT num FROM top_cardinality_error_queries(10) WHERE
+    class = (SELECT fspace_hash FROM aqo_queries WHERE
+        aqo_queries.query_hash = (SELECT aqo_query_texts.query_hash FROM aqo_query_texts
+            WHERE query_text = 'SELECT count(*) FROM (SELECT x, y FROM t2 GROUP BY GROUPING SETS ((x,y), (x), (y), ())) AS q1;'));