From fae12d5e42048805873ee8c2fb6cd6eee8ae1e3b Mon Sep 17 00:00:00 2001
From: Alexey Milovidov <milovidov@yandex-team.ru>
Date: Sun, 14 Jun 2020 04:45:03 +0300
Subject: [PATCH] Return NULL or zero when value is not parsed completely in
 parseDateTimeBestEffortOr* functions

---
 src/Functions/FunctionsConversion.h                  |  4 ++--
 ...3_parse_date_time_best_effort_null_zero.reference |  6 ++++++
 .../01313_parse_date_time_best_effort_null_zero.sql  | 12 ++++++++++++
 3 files changed, 20 insertions(+), 2 deletions(-)
 create mode 100644 tests/queries/0_stateless/01313_parse_date_time_best_effort_null_zero.reference
 create mode 100644 tests/queries/0_stateless/01313_parse_date_time_best_effort_null_zero.sql

diff --git a/src/Functions/FunctionsConversion.h b/src/Functions/FunctionsConversion.h
index 879b885cf66..83417a3229b 100644
--- a/src/Functions/FunctionsConversion.h
+++ b/src/Functions/FunctionsConversion.h
@@ -722,10 +722,10 @@ struct ConvertThroughParsing
                         parsed = ToDataType::tryReadText(vec_to[i], read_buffer, ToDataType::maxPrecision(), vec_to.getScale());
                     else
                         parsed = tryParseImpl<ToDataType>(vec_to[i], read_buffer, local_time_zone);
-
-                    parsed = parsed && isAllRead(read_buffer);
                 }
 
+                parsed = parsed && isAllRead(read_buffer);
+
                 if (!parsed)
                     vec_to[i] = 0;
 
diff --git a/tests/queries/0_stateless/01313_parse_date_time_best_effort_null_zero.reference b/tests/queries/0_stateless/01313_parse_date_time_best_effort_null_zero.reference
new file mode 100644
index 00000000000..90bb776ca10
--- /dev/null
+++ b/tests/queries/0_stateless/01313_parse_date_time_best_effort_null_zero.reference
@@ -0,0 +1,6 @@
+\N
+0000-00-00 00:00:00
+\N
+0000-00-00 00:00:00.000
+\N
+0000-00-00 00:00:00
diff --git a/tests/queries/0_stateless/01313_parse_date_time_best_effort_null_zero.sql b/tests/queries/0_stateless/01313_parse_date_time_best_effort_null_zero.sql
new file mode 100644
index 00000000000..69b66b46df7
--- /dev/null
+++ b/tests/queries/0_stateless/01313_parse_date_time_best_effort_null_zero.sql
@@ -0,0 +1,12 @@
+SELECT parseDateTimeBestEffort('<Empty>'); -- { serverError 6 }
+SELECT parseDateTimeBestEffortOrNull('<Empty>');
+SELECT parseDateTimeBestEffortOrZero('<Empty>');
+
+SELECT parseDateTime64BestEffort('<Empty>'); -- { serverError 6 }
+SELECT parseDateTime64BestEffortOrNull('<Empty>');
+SELECT parseDateTime64BestEffortOrZero('<Empty>');
+
+SET date_time_input_format = 'best_effort';
+SELECT toDateTime('<Empty>'); -- { serverError 41 }
+SELECT toDateTimeOrNull('<Empty>');
+SELECT toDateTimeOrZero('<Empty>');