diff --git a/dbms/tests/queries/0_stateless/00921_datetime64.sql b/dbms/tests/queries/0_stateless/00921_datetime64.sql
index 7d94b5fb457..2576a2b1b98 100644
--- a/dbms/tests/queries/0_stateless/00921_datetime64.sql
+++ b/dbms/tests/queries/0_stateless/00921_datetime64.sql
@@ -7,11 +7,15 @@ SELECT CAST(1 as DateTime64(100)); -- { serverError 69 } # too big scale
 SELECT CAST(1 as DateTime64(-1)); -- { serverError 43 } # signed scale parameter type
 SELECT CAST(1 as DateTime64(3, 'qqq')); -- { serverError 1000 } # invalid timezone
 
+SELECT ignore(now64());
+
 CREATE TABLE A(t DateTime64(3, 'UTC')) ENGINE = MergeTree() ORDER BY t;
-INSERT INTO A(t) VALUES (1556879125123456789), ('2019-05-03 11:25:25.123456789'), (now64(3)), (now64(6)), (now64(0));
+INSERT INTO A(t) VALUES (1556879125123456789), ('2019-05-03 11:25:25.123456789');
 
 SELECT toString(t, 'UTC'), toDate(t), toStartOfDay(t), toStartOfQuarter(t), toTime(t), toStartOfMinute(t) FROM A ORDER BY t;
 
+INSERT INTO A(t) VALUES (now64(3)), (now64(6)), (now64(0));
+
 DROP TABLE A;
  -- issue toDate does a reinterpret_cast of the datetime64 which is incorrect
 -- for the example above, it returns 2036-08-23 which is 0x5F15 days after epoch
diff --git a/dbms/tests/queries/0_stateless/00921_datetime64_compatibility.python b/dbms/tests/queries/0_stateless/00921_datetime64_compatibility.python
index 409ed472781..0cfbe4f28cb 100755
--- a/dbms/tests/queries/0_stateless/00921_datetime64_compatibility.python
+++ b/dbms/tests/queries/0_stateless/00921_datetime64_compatibility.python
@@ -98,7 +98,7 @@ extra_ops =\
             [
                 '- ', # does not work, but should it?
                 '+ ', # does not work, but should it?
-                '!=', '==', # how do we expect this to work?
+                '!=', '==', # equality and inequality supposed to take sub-second part in account
                 '< ',
                 '<=',
                 '> ',
@@ -116,7 +116,7 @@ extra_ops =\
             'op':
             [
                 '-', # does not work, but should it?
-                '!=', '==', # how do we expect this to work?
+                '!=', '==',
                 # these are naturally expected to work, but they don't:
                 '< ',
                 '<=',
@@ -158,8 +158,8 @@ extra_ops =\
 # Expand extra_ops here
 for funcs, args in extra_ops:
     args_keys = args.keys()
-    for func in funcs:
-        for args_vals in itertools.product(*args.values()):
+    for args_vals in itertools.product(*args.values()):
+        for func in funcs:
             result_func = func.format(**dict(zip(args_keys, args_vals)))
             functions.append(result_func)
 
@@ -177,11 +177,11 @@ def escape_string(s):
 # TODO: use string.Template here to allow lines that do not contain type, like: SELECT CAST(toDateTime64(1234567890), 'DateTime64')
 for func in functions:
     for dt in datetime64_args:
-        f32 = func.format(datetime='now()')
-        f64 = func.format(datetime=dt)
-        f = "({f32}) == ({f64})".format(f32=f32, f64=f64)
-        print("""SELECT '{f64}';""".format(f64=escape_string(f64)))
-        print("""SELECT {f32};""".format(f32=f32))
-        print("""SELECT {f64};""".format(f64=f64))
-#        print("""SELECT {f};""".format(f=f))
-        print("""SELECT '-----------------------------------------------------------------------------------';""")
\ No newline at end of file
+        dt32 = func.format(datetime='now()')
+        dt64 = func.format(datetime=dt)
+        f = "'values match:', ({dt32}) == ({dt64}), 'types match:', toTypeName({dt32}) == toTypeName({dt64})".format(dt32=dt32, dt64=dt64)
+        print("""SELECT 'SELECT {dt64}';""".format(dt64=escape_string(dt64)))    # for debug only
+        print("""SELECT toTypeName({dt32}), {dt32};""".format(dt32=dt32)) # for debug only
+        print("""SELECT toTypeName({dt64}), {dt64};""".format(dt64=dt64)) # for debug only
+        print("""SELECT {f};""".format(f=f))
+        print("""SELECT '------------------------------------------';""") # for debug only
\ No newline at end of file
diff --git a/dbms/tests/queries/0_stateless/00921_datetime64_compatibility.sh b/dbms/tests/queries/0_stateless/00921_datetime64_compatibility.sh
index 1ac0fe8035a..7cacbc2c165 100755
--- a/dbms/tests/queries/0_stateless/00921_datetime64_compatibility.sh
+++ b/dbms/tests/queries/0_stateless/00921_datetime64_compatibility.sh
@@ -1,8 +1,8 @@
 #!/usr/bin/env bash
 
+# We should have correct env vars from shell_config.sh to run this test
 CURDIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
 . $CURDIR/../shell_config.sh
 
-# We should have correct env vars from shell_config.sh to run this test
-
-python $CURDIR/00921_datetime64_compatibility.python | ${CLICKHOUSE_CLIENT} -nm
\ No newline at end of file
+# in order to check queries individually (does not stop on the first one that fails):
+IFS=$'\n'; for I in $($CURDIR/00921_datetime64_compatibility.python) ; do "${CLICKHOUSE_CLIENT}" -nm -q "$I"; echo ; done # 2>&1 | tee datetime64_compat.log