MDEV-7970: EXPLAIN FORMAT=JSON does not print HAVING

Printing non-trivial HAVING added.

1 files changed, 23 insertions, 1 deletions

diff --git a/mysql-test/t/explain_json.test b/mysql-test/t/explain_json.test
index 1078222725e..4279d3b4fb4 100644
--- a/mysql-test/t/explain_json.test
+++ b/mysql-test/t/explain_json.test
@@ -278,7 +278,6 @@ explain format=json select count(distinct a1,a2,b,c) from t1 where (a2 >= 'b') a
 
 drop table t1;
 
-
 --echo #
 --echo # MDEV-8786 Wrong result for SELECT FORMAT=JSON * FROM t1 WHERE a=_latin1 0xDF
 --echo #
@@ -294,3 +293,26 @@ CREATE TABLE t1 (a VARCHAR(10) CHARACTER SET latin1);
 INSERT INTO t1 VALUES ('a'),('A');
 EXPLAIN FORMAT=JSON SELECT * FROM t1 WHERE NULLIF(a,_utf8'a' COLLATE utf8_bin);
 DROP TABLE t1;
+
+--echo #
+--echo # MDEV-7970: EXPLAIN FORMAT=JSON does not print HAVING
+--echo #
+create table t0(a int);
+insert into t0 values (0),(1),(2),(3);
+create table t1(a int);
+insert into t1 select A.a + B.a* 10 + C.a * 100 from t0 A, t0 B, t0 C;
+create table t2 (
+  a int, 
+  b int, 
+  key (a)
+);
+insert into t2 select A.a*1000 + B.a, A.a*1000 + B.a from t0 A, t1 B;
+--echo # normal HAVING
+explain format=json select a, max(b) as TOP from t2 group by a having TOP > a;
+--echo # HAVING is always TRUE (not printed)
+explain format=json select a, max(b) as TOP from t2 group by a having 1<>2;
+--echo # HAVING is always FALSE (intercepted by message)
+explain format=json select a, max(b) as TOP from t2 group by a having 1=2;
+--echo # HAVING is absent
+explain format=json select a, max(b) as TOP from t2 group by a;
+drop table t0, t1, t2;