Add test cases for auto_explain and enable it in GNUmakefile.in (#7195)

1. Add test cases for auto_explain
	* Add init_file to filter out random numbers
	* set CLIENT_MIN_MESSAGES to show `LOG` message to result file
2. Add auto_explain item in gpdb/GNUmakefile.in

GNUmakefile.in

@@ -11,6 +11,7 @@ include $(top_builddir)/src/Makefile.global
 $(call recurse,all install,src config)
 
 all:
+	$(MAKE) -C contrib/auto_explain all
 	$(MAKE) -C contrib/file_fdw all
 	$(MAKE) -C contrib/formatter all
 	$(MAKE) -C contrib/formatter_fixedwidth all
@@ -44,6 +45,7 @@ html man:
 	$(MAKE) -C doc $@
 
 install:
+	$(MAKE) -C contrib/auto_explain $@
 	#$(MAKE) -C contrib/file_fdw $@ # GPDB_91_MERGE_FIXME: disable installation until it's officially supported.
 	$(MAKE) -C contrib/formatter $@
 	$(MAKE) -C contrib/formatter_fixedwidth $@
@@ -139,6 +141,7 @@ $(call recurse,installcheck-world, \
 			   src/test/ \
 			   src/pl \
 			   src/interfaces/gppc \
+			   contrib/auto_explain \
 			   contrib/formatter_fixedwidth \
 			   contrib/extprotocol \
 			   contrib/dblink \

contrib/auto_explain/Makefile

@@ -3,6 +3,9 @@
 MODULE_big = auto_explain
 OBJS = auto_explain.o
 
+REGRESS = auto_explain
+REGRESS_OPTS = --init-file=init_file
+
 ifdef USE_PGXS
 PG_CONFIG = pg_config
 PGXS := $(shell $(PG_CONFIG) --pgxs)

contrib/auto_explain/expected/auto_explain.out

+SET CLIENT_MIN_MESSAGES = LOG;
+LOAD 'auto_explain';
+LOG:  statement: LOAD 'auto_explain';
+SET auto_explain.log_analyze = TRUE;
+LOG:  statement: SET auto_explain.log_analyze = TRUE;
+SET auto_explain.log_min_duration = 0;
+LOG:  statement: SET auto_explain.log_min_duration = 0;
+SET auto_explain.log_buffers = FALSE;
+LOG:  statement: SET auto_explain.log_buffers = FALSE;
+SET auto_explain.log_triggers = TRUE;
+LOG:  statement: SET auto_explain.log_triggers = TRUE;
+SET auto_explain.log_nested_statements = FALSE;
+LOG:  statement: SET auto_explain.log_nested_statements = FALSE;
+SET auto_explain.log_timing = FALSE;
+LOG:  statement: SET auto_explain.log_timing = FALSE;
+SET auto_explain.log_verbose = FALSE;
+LOG:  statement: SET auto_explain.log_verbose = FALSE;
+SELECT relname FROM pg_class WHERE relname='pg_class';
+LOG:  statement: SELECT relname FROM pg_class WHERE relname='pg_class';
+LOG:  duration: 0.198 ms  plan:
+Query Text: SELECT relname FROM pg_class WHERE relname='pg_class';
+Seq Scan on pg_class  (cost=0.00..11.46 rows=1 width=64) (actual rows=1 loops=1)
+  Filter: (relname = 'pg_class'::name)
+  Rows Removed by Filter: 436
+  (slice0)    Executor memory: 32K bytes.
+Memory used:  128000kB
+ relname  
+----------
+ pg_class
+(1 row)
+
+SELECT count(*)>0 FROM pg_class, pg_index WHERE oid = indrelid AND indisunique;
+LOG:  statement: SELECT count(*)>0 FROM pg_class, pg_index WHERE oid = indrelid AND indisunique;
+LOG:  duration: 5.369 ms  plan:
+Query Text: SELECT count(*)>0 FROM pg_class, pg_index WHERE oid = indrelid AND indisunique;
+Aggregate  (cost=19.62..19.64 rows=1 width=1) (actual rows=1 loops=1)
+  ->  Hash Join  (cost=4.29..19.29 rows=135 width=0) (actual rows=135 loops=1)
+        Hash Cond: (pg_class.oid = pg_index.indrelid)
+        Extra Text: Hash chain length 1.5 avg, 3 max, using 91 of 524288 buckets.
+        ->  Seq Scan on pg_class  (cost=0.00..10.37 rows=437 width=4) (actual rows=437 loops=1)
+        ->  Hash  (cost=2.60..2.60 rows=45 width=4) (actual rows=135 loops=1)
+              Buckets: 524288  Batches: 1  Memory Usage: 4kB
+              ->  Seq Scan on pg_index  (cost=0.00..2.60 rows=135 width=4) (actual rows=135 loops=1)
+                    Filter: indisunique
+                    Rows Removed by Filter: 25
+  (slice0)    Executor memory: 4177K bytes.  Work_mem: 4K bytes max.
+Memory used:  128000kB
+ ?column? 
+----------
+ t
+(1 row)
+
+SET auto_explain.log_min_duration = 1;
+LOG:  statement: SET auto_explain.log_min_duration = 1;
+SET auto_explain.log_triggers = FALSE;
+LOG:  statement: SET auto_explain.log_triggers = FALSE;
+SET auto_explain.log_verbose = TRUE;
+LOG:  statement: SET auto_explain.log_verbose = TRUE;
+SELECT relname FROM pg_class WHERE relname='pg_class';
+LOG:  statement: SELECT relname FROM pg_class WHERE relname='pg_class';
+ relname  
+----------
+ pg_class
+(1 row)
+
+SELECT count(*)>0 FROM pg_class, pg_index WHERE oid = indrelid AND indisunique;
+LOG:  statement: SELECT count(*)>0 FROM pg_class, pg_index WHERE oid = indrelid AND indisunique;
+LOG:  duration: 4.530 ms  plan:
+Query Text: SELECT count(*)>0 FROM pg_class, pg_index WHERE oid = indrelid AND indisunique;
+Aggregate  (cost=19.62..19.64 rows=1 width=1) (actual rows=1 loops=1)
+  Output: (count(*) > 0)
+  ->  Hash Join  (cost=4.29..19.29 rows=135 width=0) (actual rows=135 loops=1)
+        Hash Cond: (pg_class.oid = pg_index.indrelid)
+        Executor Memory: 4kB  Segments: 1  Max: 4kB (segment -1)
+        work_mem: 4kB  Segments: 1  Max: 4kB (segment -1)  Workfile: (0 spilling)
+        Extra Text: Hash chain length 1.5 avg, 3 max, using 91 of 524288 buckets.
+        ->  Seq Scan on pg_catalog.pg_class  (cost=0.00..10.37 rows=437 width=4) (actual rows=437 loops=1)
+              Output: pg_class.oid
+        ->  Hash  (cost=2.60..2.60 rows=45 width=4) (actual rows=135 loops=1)
+              Output: pg_index.indrelid
+              Buckets: 524288  Batches: 1  Memory Usage: 4kB
+              ->  Seq Scan on pg_catalog.pg_index  (cost=0.00..2.60 rows=135 width=4) (actual rows=135 loops=1)
+                    Output: pg_index.indrelid
+                    Filter: pg_index.indisunique
+                    Rows Removed by Filter: 25
+  (slice0)    Executor memory: 4177K bytes.  Work_mem: 4K bytes max.
+Memory used:  128000kB
+ ?column? 
+----------
+ t
+(1 row)
+

contrib/auto_explain/init_file

+-- start_matchsubs
+
+m/\(cost=[a-z_A-Z0-9. =]+\)\s+\([a-z_A-Z0-9. =]+\)/
+s/\(cost=[a-z_A-Z0-9. =]+\)\s+\([a-z_A-Z0-9. =]+\)//
+
+m/duration:.*$/
+s/duration:\s+[0-9.]+\s*ms.*/duration: ms/
+
+m/Rows Removed by Filter: .*/
+s/Rows Removed by Filter: .*/Rows Removed by Filter: /
+
+m/Executor [mM]emory: .*/
+s/Executor [mM]emory: .*/Executor Memory: /
+
+m/Memory used:\s+[0-9kKmMgGB]+/
+s/Memory used:\s+[0-9kKmMgGB]+/Memory used:/
+
+m/Buckets: [0-9]+\s+Batches: [0-9]+\s+Memory Usage:\s+[0-9kKmMgG]B/
+s/Buckets: [0-9]+\s+Batches: [0-9]+\s+Memory Usage:\s+[0-9kKmMgG]B/Buckets: 524288  Batches: 1  Memory Usage: 4kB/
+
+m/Extra Text: Hash chain length [0-9.]+ avg, [0-9]+ max, using [0-9]+ of [0-9]+ buckets/
+s/Extra Text: Hash chain length [0-9.]+ avg, [0-9]+ max, using [0-9]+ of [0-9]+ buckets/Extra Text: Hash chain length 1.5 avg, 3 max, using 91 of 524288 buckets/
+
+m/work_mem: [0-9kKmMgG]B  Segments: [-0-9]+  Max: [0-9kKmMgG]+B.*/
+s/work_mem: [0-9kKmMgG]B  Segments: [-0-9]+  Max: [0-9kKmMgG]+B.*/work_mem: 4kB  Segments: 1  Max: 4kB/
+-- end_matchsubs
+
+-- start_matchignore
+# orca failed to produce the expected plan, ignore this message
+m/LOG:  Planner produced plan :0/
+-- end_matchignore

contrib/auto_explain/sql/auto_explain.sql

+SET CLIENT_MIN_MESSAGES = LOG;
+LOAD 'auto_explain';
+SET auto_explain.log_analyze = TRUE;
+SET auto_explain.log_min_duration = 0;
+SET auto_explain.log_buffers = FALSE;
+SET auto_explain.log_triggers = TRUE;
+SET auto_explain.log_nested_statements = FALSE;
+SET auto_explain.log_timing = FALSE;
+SET auto_explain.log_verbose = FALSE;
+
+SELECT relname FROM pg_class WHERE relname='pg_class';
+SELECT count(*)>0 FROM pg_class, pg_index WHERE oid = indrelid AND indisunique;
+
+SET auto_explain.log_min_duration = 1;
+SET auto_explain.log_triggers = FALSE;
+SET auto_explain.log_verbose = TRUE;
+
+SELECT relname FROM pg_class WHERE relname='pg_class';
+SELECT count(*)>0 FROM pg_class, pg_index WHERE oid = indrelid AND indisunique;