DateTime comparison with date string literal

2024-12-03 13:02:00 +00:00 · 2020-10-17 00:31:29 +03:00 · 2020-10-17 00:31:29 +03:00 · 02da9af32d
commit 02da9af32d
parent 4eb684603a
6 changed files with 231 additions and 16 deletions
--- a/docs/en/operations/settings/settings.md
+++ b/docs/en/operations/settings/settings.md
@ -384,7 +384,7 @@ Possible values:

 -   `'basic'` — Use basic parser.

-    ClickHouse can parse only the basic `YYYY-MM-DD HH:MM:SS` format. For example, `'2019-08-20 10:18:56'`.
+    ClickHouse can parse only the basic `YYYY-MM-DD HH:MM:SS` or `YYYY-MM-DD` format. For example, `'2019-08-20 10:18:56'` or `2019-08-20`.

 Default value: `'basic'`.

--- a/docs/en/sql-reference/data-types/date.md
+++ b/docs/en/sql-reference/data-types/date.md
@ -3,10 +3,45 @@ toc_priority: 47
 toc_title: Date
 ---

-# Date {#date}
+# Date {#data_type-date}

 A date. Stored in two bytes as the number of days since 1970-01-01 (unsigned). Allows storing values from just after the beginning of the Unix Epoch to the upper threshold defined by a constant at the compilation stage (currently, this is until the year 2106, but the final fully-supported year is 2105).

 The date value is stored without the time zone.

+## Examples {#examples}
+
+**1.** Creating a table with a `DateTime`-type column and inserting data into it:
+
+``` sql
+CREATE TABLE dt
+(
+    `timestamp` Date,
+    `event_id` UInt8
+)
+ENGINE = TinyLog;
+```
+
+``` sql
+INSERT INTO dt Values (1546300800, 1), ('2019-01-01', 2);
+```
+
+``` sql
+SELECT * FROM dt;
+```
+
+``` text
+┌──timestamp─┬─event_id─┐
+│ 2019-01-01 │        1 │
+│ 2019-01-01 │        2 │
+└────────────┴──────────┘
+```
+
+## See Also {#see-also}
+
+-   [Functions for working with dates and times](../../sql-reference/functions/date-time-functions.md)
+-   [Operators for working with dates and times](../../sql-reference/operators/index.md#operators-datetime)
+-   [`DateTime` data type](../../sql-reference/data-types/datetime.md)
+
+
 [Original article](https://clickhouse.tech/docs/en/data_types/date/) <!--hide-->
--- a/src/IO/ReadHelpers.cpp
+++ b/src/IO/ReadHelpers.cpp
@ -817,7 +817,11 @@ ReturnType readDateTimeTextFallback(time_t & datetime, ReadBuffer & buf, const D
 {
    static constexpr bool throw_exception = std::is_same_v<ReturnType, void>;

+    /// YYYY-MM-DD hh:mm:ss
    static constexpr auto date_time_broken_down_length = 19;
+    /// YYYY-MM-DD
+    static constexpr auto date_broken_down_length = 10;
+    /// unix timestamp max length
    static constexpr auto unix_timestamp_max_length = 10;

    char s[date_time_broken_down_length];
@ -831,12 +835,15 @@ ReturnType readDateTimeTextFallback(time_t & datetime, ReadBuffer & buf, const D
        ++buf.position();
    }

-    /// 2015-01-01 01:02:03
+    /// 2015-01-01 01:02:03 or 2015-01-01
    if (s_pos == s + 4 && !buf.eof() && (*buf.position() < '0' || *buf.position() > '9'))
    {
-        const size_t remaining_size = date_time_broken_down_length - (s_pos - s);
-        size_t size = buf.read(s_pos, remaining_size);
-        if (remaining_size != size)
+        const auto already_read_length = s_pos - s;
+        const size_t remaining_date_time_size = date_time_broken_down_length - already_read_length;
+        const size_t remaining_date_size = date_broken_down_length - already_read_length;
+
+        size_t size = buf.read(s_pos, remaining_date_time_size);
+        if (size != remaining_date_time_size && size != remaining_date_size)
        {
            s_pos[size] = 0;

@ -850,9 +857,16 @@ ReturnType readDateTimeTextFallback(time_t & datetime, ReadBuffer & buf, const D
        UInt8 month = (s[5] - '0') * 10 + (s[6] - '0');
        UInt8 day = (s[8] - '0') * 10 + (s[9] - '0');

-        UInt8 hour = (s[11] - '0') * 10 + (s[12] - '0');
-        UInt8 minute = (s[14] - '0') * 10 + (s[15] - '0');
-        UInt8 second = (s[17] - '0') * 10 + (s[18] - '0');
+        UInt8 hour = 0;
+        UInt8 minute = 0;
+        UInt8 second = 0;
+
+        if (size == remaining_date_time_size)
+        {
+            hour = (s[11] - '0') * 10 + (s[12] - '0');
+            minute = (s[14] - '0') * 10 + (s[15] - '0');
+            second = (s[17] - '0') * 10 + (s[18] - '0');
+        }

        if (unlikely(year == 0))
            datetime = 0;
--- a/src/IO/ReadHelpers.h
+++ b/src/IO/ReadHelpers.h
@ -700,7 +700,7 @@ UInt128 stringToUUID(const String & str);
 template <typename ReturnType = void>
 ReturnType readDateTimeTextFallback(time_t & datetime, ReadBuffer & buf, const DateLUTImpl & date_lut);

-/** In YYYY-MM-DD hh:mm:ss format, according to specified time zone.
+/** In YYYY-MM-DD hh:mm:ss or YYYY-MM-DD format, according to specified time zone.
  * As an exception, also supported parsing of unix timestamp in form of decimal number.
  */
 template <typename ReturnType = void>
@ -709,12 +709,21 @@ inline ReturnType readDateTimeTextImpl(time_t & datetime, ReadBuffer & buf, cons
    /** Read 10 characters, that could represent unix timestamp.
      * Only unix timestamp of 5-10 characters is supported.
      * Then look at 5th character. If it is a number - treat whole as unix timestamp.
-      * If it is not a number - then parse datetime in YYYY-MM-DD hh:mm:ss format.
+      * If it is not a number - then parse datetime in YYYY-MM-DD hh:mm:ss or YYYY-MM-DD format.
      */

    /// Optimistic path, when whole value is in buffer.
    const char * s = buf.position();
-    if (s + 19 <= buf.buffer().end())
+
+    /// YYYY-MM-DD hh:mm:ss
+    static constexpr auto DateTimeStringInputSize = 19;
+    bool optimistic_path_for_date_time_input = s + DateTimeStringInputSize <= buf.buffer().end();
+
+    /// YYYY-MM-DD
+    static constexpr auto DateStringInputSize = 10;
+    bool optimistic_path_for_date_input = s + DateStringInputSize <= buf.buffer().end();
+
+    if (optimistic_path_for_date_time_input || optimistic_path_for_date_input)
    {
        if (s[4] < '0' || s[4] > '9')
        {
@ -722,16 +731,23 @@ inline ReturnType readDateTimeTextImpl(time_t & datetime, ReadBuffer & buf, cons
            UInt8 month = (s[5] - '0') * 10 + (s[6] - '0');
            UInt8 day = (s[8] - '0') * 10 + (s[9] - '0');

-            UInt8 hour = (s[11] - '0') * 10 + (s[12] - '0');
-            UInt8 minute = (s[14] - '0') * 10 + (s[15] - '0');
-            UInt8 second = (s[17] - '0') * 10 + (s[18] - '0');
+            UInt8 hour = 0;
+            UInt8 minute = 0;
+            UInt8 second = 0;
+
+            if (optimistic_path_for_date_time_input)
+            {
+                hour = (s[11] - '0') * 10 + (s[12] - '0');
+                minute = (s[14] - '0') * 10 + (s[15] - '0');
+                second = (s[17] - '0') * 10 + (s[18] - '0');
+            }

            if (unlikely(year == 0))
                datetime = 0;
            else
                datetime = date_lut.makeDateTime(year, month, day, hour, minute, second);

-            buf.position() += 19;
+            buf.position() += optimistic_path_for_date_time_input ? DateTimeStringInputSize : DateStringInputSize;
            return ReturnType(true);
        }
        else
--- a/tests/queries/0_stateless/01523_date_time_compare_with_date_literal.reference
+++ b/tests/queries/0_stateless/01523_date_time_compare_with_date_literal.reference
@ -0,0 +1,80 @@
+DateTime
+2020-10-15 12:00:00
+2020-10-16 00:00:00
+
+2020-10-15 00:00:00
+
+2020-10-15 12:00:00
+2020-10-16 00:00:00
+
+2020-10-15 00:00:00
+2020-10-15 12:00:00
+2020-10-16 00:00:00
+
+2020-10-15 00:00:00
+2020-10-15 12:00:00
+
+2020-10-15 00:00:00
+2020-10-15 12:00:00
+2020-10-16 00:00:00
+
+
+2020-10-15 12:00:00
+2020-10-16 00:00:00
+
+2020-10-15 00:00:00
+
+2020-10-15 12:00:00
+2020-10-16 00:00:00
+
+2020-10-15 00:00:00
+2020-10-15 12:00:00
+2020-10-16 00:00:00
+
+2020-10-15 00:00:00
+2020-10-15 12:00:00
+
+2020-10-15 00:00:00
+2020-10-15 12:00:00
+2020-10-16 00:00:00
+
+DateTime64
+2020-10-15 12:00:00.000
+2020-10-16 00:00:00.000
+
+2020-10-15 00:00:00.000
+
+2020-10-15 12:00:00.000
+2020-10-16 00:00:00.000
+
+2020-10-15 00:00:00.000
+2020-10-15 12:00:00.000
+2020-10-16 00:00:00.000
+
+2020-10-15 00:00:00.000
+2020-10-15 12:00:00.000
+
+2020-10-15 00:00:00.000
+2020-10-15 12:00:00.000
+2020-10-16 00:00:00.000
+
+
+2020-10-15 12:00:00.000
+2020-10-16 00:00:00.000
+
+2020-10-15 00:00:00.000
+
+2020-10-15 12:00:00.000
+2020-10-16 00:00:00.000
+
+2020-10-15 00:00:00.000
+2020-10-15 12:00:00.000
+2020-10-16 00:00:00.000
+
+2020-10-15 00:00:00.000
+2020-10-15 12:00:00.000
+
+2020-10-15 00:00:00.000
+2020-10-15 12:00:00.000
+2020-10-16 00:00:00.000
+
--- a/tests/queries/0_stateless/01523_date_time_compare_with_date_literal.sql
+++ b/tests/queries/0_stateless/01523_date_time_compare_with_date_literal.sql
@ -0,0 +1,70 @@
+DROP TABLE IF EXISTS test;
+
+CREATE TABLE test(timestamp DateTime) ENGINE = MergeTree ORDER BY timestamp;
+
+INSERT INTO test VALUES ('2020-10-15 00:00:00');
+INSERT INTO test VALUES ('2020-10-15 12:00:00');
+INSERT INTO test VALUES ('2020-10-16 00:00:00');
+
+SELECT 'DateTime';
+SELECT * FROM test WHERE timestamp != '2020-10-15' ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE timestamp == '2020-10-15' ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE timestamp > '2020-10-15' ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE timestamp >= '2020-10-15' ORDER by timestamp;
+SELECT '';
+SELECT * FROM test WHERE timestamp < '2020-10-16' ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE timestamp <= '2020-10-16' ORDER BY timestamp;
+SELECT '';
+SELECT '';
+SELECT * FROM test WHERE '2020-10-15' != timestamp ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE '2020-10-15' == timestamp ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE '2020-10-15' < timestamp ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE '2020-10-15' <= timestamp ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE '2020-10-16' > timestamp ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE '2020-10-16' >= timestamp ORDER BY timestamp;
+SELECT '';
+
+DROP TABLE test;
+CREATE TABLE test(timestamp DateTime64) ENGINE = MergeTree ORDER BY timestamp;
+
+INSERT INTO test VALUES ('2020-10-15 00:00:00');
+INSERT INTO test VALUES ('2020-10-15 12:00:00');
+INSERT INTO test VALUES ('2020-10-16 00:00:00');
+
+SELECT 'DateTime64';
+SELECT * FROM test WHERE timestamp != '2020-10-15' ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE timestamp == '2020-10-15' ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE timestamp > '2020-10-15' ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE timestamp >= '2020-10-15' ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE timestamp < '2020-10-16' ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE timestamp <= '2020-10-16' ORDER BY timestamp;
+SELECT '';
+SELECT '';
+SELECT * FROM test WHERE '2020-10-15' != timestamp ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE '2020-10-15' == timestamp ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE '2020-10-15' < timestamp ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE '2020-10-15' <= timestamp ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE '2020-10-16' > timestamp ORDER BY timestamp;
+SELECT '';
+SELECT * FROM test WHERE '2020-10-16' >= timestamp ORDER BY timestamp;
+SELECT '';
+
+DROP TABLE test;