Make reader_waits_for_lock test more readable

Author: Xin Zhang <xzhang@pivotal.io>
Author: Ashwin Agrawal <aagrawal@pivotal.io>

src/test/isolation2/expected/reader_waits_for_lock.out

@@ -3,28 +3,28 @@
 -- held by some other session.
 
 -- setup
-5: create table reader_waits_for_lock_table(a int, b int) distributed by (a);
+1: create table reader_waits_for_lock_table(a int, b int) distributed by (a);
 CREATE
-5: insert into reader_waits_for_lock_table select 1, 1;
+1: insert into reader_waits_for_lock_table select 1, 1;
 INSERT 1
 -- save session id
-5: CREATE TABLE reader_waits_for_lock_table_sessionid(a, setting) AS SELECT 1, setting::int FROM pg_settings WHERE name = 'gp_session_id' distributed by (a);
+1: CREATE TABLE reader_waits_for_lock_table_sessionid(a, setting) AS SELECT 1, setting::int FROM pg_settings WHERE name = 'gp_session_id' distributed by (a);
 CREATE 1
 2U: BEGIN;
 BEGIN
 2U: LOCK reader_waits_for_lock_table IN ACCESS EXCLUSIVE MODE;
 LOCK
 -- creates reader and writer gang
-5&: SELECT t1.* FROM reader_waits_for_lock_table t1 INNER JOIN reader_waits_for_lock_table t2 ON t1.b = t2.b;  <waiting ...>
--- all processes in the session 5 should be blocked
-2U: SELECT count(case when not waiting then 1 end), count(*) > 0 FROM pg_stat_activity where sess_id = (SELECT setting FROM reader_waits_for_lock_table_sessionid);
-count|?column?
------+--------
-0    |t       
+1&: SELECT t1.* FROM reader_waits_for_lock_table t1 INNER JOIN reader_waits_for_lock_table t2 ON t1.b = t2.b;  <waiting ...>
+-- all processes in the session 1 should be blocked
+2U: SELECT count(case when waiting then 1 end) = count(*) all_waiting FROM pg_stat_activity where sess_id = (SELECT setting FROM reader_waits_for_lock_table_sessionid);
+all_waiting
+-----------
+t          
 (1 row)
 2U: COMMIT;
 COMMIT
-5<:  <... completed>
+1<:  <... completed>
 a|b
 -+-
 1|1

src/test/isolation2/sql/reader_waits_for_lock.sql

@@ -3,15 +3,15 @@
 -- held by some other session.
 
 -- setup
-5: create table reader_waits_for_lock_table(a int, b int) distributed by (a);
-5: insert into reader_waits_for_lock_table select 1, 1;
+1: create table reader_waits_for_lock_table(a int, b int) distributed by (a);
+1: insert into reader_waits_for_lock_table select 1, 1;
 -- save session id
-5: CREATE TABLE reader_waits_for_lock_table_sessionid(a, setting) AS SELECT 1, setting::int FROM pg_settings WHERE name = 'gp_session_id' distributed by (a);
+1: CREATE TABLE reader_waits_for_lock_table_sessionid(a, setting) AS SELECT 1, setting::int FROM pg_settings WHERE name = 'gp_session_id' distributed by (a);
 2U: BEGIN;
 2U: LOCK reader_waits_for_lock_table IN ACCESS EXCLUSIVE MODE;
 -- creates reader and writer gang
-5&: SELECT t1.* FROM reader_waits_for_lock_table t1 INNER JOIN reader_waits_for_lock_table t2 ON t1.b = t2.b;
--- all processes in the session 5 should be blocked
-2U: SELECT count(case when not waiting then 1 end), count(*) > 0 FROM pg_stat_activity where sess_id = (SELECT setting FROM reader_waits_for_lock_table_sessionid);
+1&: SELECT t1.* FROM reader_waits_for_lock_table t1 INNER JOIN reader_waits_for_lock_table t2 ON t1.b = t2.b;
+-- all processes in the session 1 should be blocked
+2U: SELECT count(case when waiting then 1 end) = count(*) all_waiting FROM pg_stat_activity where sess_id = (SELECT setting FROM reader_waits_for_lock_table_sessionid);
 2U: COMMIT;
-5<:
+1<: