HOUR_CEIL

Description

The hour_ceil function rounds up the input datetime value to the nearest moment of the specified hour period. For example, if the period is 5 hours, the function adjusts the input time to the next hour mark within that period.

Date calculation formula:

$$\begin{aligned} &\text{hour\_ceil}(\langle\text{date\_or\_time\_expr}\rangle, \langle\text{period}\rangle, \langle\text{origin}\rangle) = \\ &\min\{\langle\text{origin}\rangle + k \times \langle\text{period}\rangle \times \text{hour} \mid \\ &k \in \mathbb{Z} \land \langle\text{origin}\rangle + k \times \langle\text{period}\rangle \times \text{hour} \geq \langle\text{date\_or\_time\_expr}\rangle\} \end{aligned}$$

$k$ represents the number of periods required from the baseline time to reach the target time.

Syntax

HOUR_CEIL(`<date_or_time_expr>`)
HOUR_CEIL(`<date_or_time_expr>`, `<origin>`)
HOUR_CEIL(`<date_or_time_expr>`, `<period>`)
HOUR_CEIL(`<date_or_time_expr>`, `<period>`, `<origin>`)

Parameters

Parameter	Description
<date_or_time_expr>	A valid date expression that supports datetime and date types. Date type will be converted to the start of the day at 00:00:00. For specific datetime/date formats, please refer to datetime conversion and date conversion
<period>	Optional parameter that specifies the period length (unit: hours), must be a positive integer (such as 1, 3, 5). Default value is 1, representing one period every 1 hour
<origin>	The starting time origin, supports datetime and date types. If not provided, the default is 0001-01-01T00:00:00

Return Value

Returns a DATETIME type value representing the nearest period moment after rounding up.

• If the input period is a non-positive integer, returns an error.
• If any parameter is NULL, the result returns NULL.
• If origin or datetime has scale, the returned result has scale.
• If the calculation result exceeds the maximum datetime range 9999-12-31 23:59:59, returns an error.
• If the date and time is after the , it will still be calculated according to the above formula, but the period k will be negative.

Examples

-- Round up with a 5-hour period
mysql> select hour_ceil("2023-07-13 22:28:18", 5);
+-------------------------------------+
| hour_ceil("2023-07-13 22:28:18", 5) |
+-------------------------------------+
| 2023-07-13 23:00:00                 |
+-------------------------------------+

-- Using 2023-07-13 08:00 as the origin, divide by 4-hour periods
mysql> select hour_ceil('2023-07-13 19:30:00', 4, '2023-07-13 08:00:00') as custom_origin;
+----------------------------+
| custom_origin              |
+----------------------------+
| 2023-07-13 20:00:00        |
+----------------------------+

-- Input date type will be converted to the start time 00:00:00 of the corresponding date
mysql> select hour_ceil('2023-07-13 00:30:00', 6, '2023-07-13');
+---------------------------------------------------+
| hour_ceil('2023-07-13 00:30:00', 6, '2023-07-13') |
+---------------------------------------------------+
| 2023-07-13 06:00:00                               |
+---------------------------------------------------+

-- If exactly at the edge of a period, return the input datetime
select hour_ceil('2023-07-13 01:00:00');
+----------------------------------+
| hour_ceil('2023-07-13 01:00:00') |
+----------------------------------+
| 2023-07-13 01:00:00              |
+----------------------------------+

-- If origin or datetime has scale, the returned result has scale
mysql> select hour_ceil('2023-07-13 19:30:00', 4, '2023-07-13 08:00:00.123') ;
+----------------------------------------------------------------+
| hour_ceil('2023-07-13 19:30:00', 4, '2023-07-13 08:00:00.123') |
+----------------------------------------------------------------+
| 2023-07-13 20:00:00.123                                        |
+----------------------------------------------------------------+

mysql> select hour_ceil('2023-07-13 19:30:00.123', 4, '2023-07-13 08:00:00') ;
+----------------------------------------------------------------+
| hour_ceil('2023-07-13 19:30:00.123', 4, '2023-07-13 08:00:00') |
+----------------------------------------------------------------+
| 2023-07-13 20:00:00.000                                        |
+----------------------------------------------------------------+

--- If the <origin> date and time is after the <period>, it will still be calculated according to the above formula, but the period k will be negative.
select hour_ceil('2023-07-13 19:30:00.123', 4, '2028-07-14 08:00:00') ;
+----------------------------------------------------------------+
| hour_ceil('2023-07-13 19:30:00.123', 4, '2028-07-14 08:00:00') |
+----------------------------------------------------------------+
| 2023-07-13 20:00:00.000                                        |
+----------------------------------------------------------------+

-- If calculation result exceeds maximum datetime range 9999-12-31 23:59:59, return NULL
select hour_ceil("9999-12-31 22:28:18", 6);
ERROR 1105 (HY000): errCode = 2, detailMessage = (10.16.10.3)[E-218]Operation hour_ceil of 9999-12-31 22:28:18, 6 out of range

-- If period is less than or equal to 0, return error
mysql> select hour_ceil("2023-07-13 22:28:18", 0);
ERROR 1105 (HY000): errCode = 2, detailMessage = (10.16.10.3)[E-218]Operation hour_ceil of 2023-07-13 22:28:18, 0 out of range

-- If any input parameter is NULL, return NULL
mysql> select hour_ceil(null, 3) as null_input;
+------------+
| null_input |
+------------+
| NULL       |
+------------+

mysql> select hour_ceil("2023-07-13 22:28:18", NULL);
+----------------------------------------+
| hour_ceil("2023-07-13 22:28:18", NULL) |
+----------------------------------------+
| NULL                                   |
+----------------------------------------+

mysql> select hour_ceil("2023-07-13 22:28:18", 5,NULL);
+------------------------------------------+
| hour_ceil("2023-07-13 22:28:18", 5,NULL) |
+------------------------------------------+
| NULL                                     |
+------------------------------------------+