Convert strings to date values with TO_DATE - MaxCompute

Converts a string into a DATE or DATETIME value using a specified format pattern.

Syntax

DATETIME|DATE TO_DATE(STRING <date>[, STRING <format>])

Parameters

Parameter	Required	Type	Description
`date`	Yes	STRING	The string to convert. BIGINT, DOUBLE, DECIMAL, and DATETIME values are implicitly converted to STRING before processing. ISO 8601 format strings are also supported.
`format`	No	STRING (constant)	The format pattern to apply. Does not support date extension formats. Characters not recognized as format specifiers are ignored during parsing. Must contain `yyyy`, and `yyyy` can appear only once. If this condition is not met, the function returns NULL.

Format specifiers

Specifier	Meaning	Example value
`yyyy`	Four-digit year	`2025`
`mm`	Two-digit month	`01`
`dd`	Two-digit day	`29`
`hh`	Hour (24-hour clock)	`15`
`mi`	Two-digit minute	`13`
`ss`	Two-digit second	`12`
`ff3`	Three-digit millisecond	`345`

Return value

Condition	Return type	Format
Called without `format`	DATE	`yyyy-mm-dd`
Called with `format`	DATETIME	`yyyy-mm-dd hh:mi:ss`
`date` or `format` is NULL	NULL	—

Examples

Basic usage (no format)

-- Returns 2025-01-29
SELECT TO_DATE('2025-01-29');

Custom format strings

All examples below use the format parameter and return a DATETIME value.

-- Returns 2025-01-27 00:00:00
SELECT TO_DATE('Alibaba2025-01*27', 'Alibabayyyy-mm*dd');

-- Returns 2025-01-12 00:00:00
SELECT TO_DATE('20250112', 'yyyymmdd');

-- Returns 2025-01-28 12:12:00
SELECT TO_DATE('202501281212', 'yyyymmddhhmi');

-- Returns 2025-10-30 15:13:12
SELECT TO_DATE('20251030 15-13-12.345', 'yyyymmdd hh-mi-ss.ff3');

ISO 8601 format

-- Returns 2025-09-24 13:39:34
SELECT TO_DATE('2025-09-24T13:39:34.119Z', 'yyyy-MM-ddThh:mi:ss.ff3Z');

NULL inputs

-- Returns NULL
SELECT TO_DATE(NULL, 'yyyymmdd hh-mi-ss.ff3');

-- Returns NULL
SELECT TO_DATE('20251030 15-13-12.345', NULL);

Invalid inputs

-- Returns NULL. '2025112' does not match 'yyyymmdd' (day is missing a digit; use '20250112')
SELECT TO_DATE('2025112', 'yyyymmdd');

-- Returns NULL. Day value '3' is not two digits (use 'Alibaba2025-12*03')
SELECT TO_DATE('Alibaba2025-12*3', 'Alibabayyyy-mm*dd');

-- Returns NULL. '2025-24-01' cannot be converted to a standard date value. It should be '2025-01-24'.
SELECT TO_DATE('2025-24-01', 'yyyy');

Table data example

Create the example table and insert data.

CREATE TABLE IF NOT EXISTS mf_date_fun_t(
    id        INT,
    date1     DATE,
    datetime1 DATETIME,
    timestamp1 TIMESTAMP,
    date2     DATE,
    datetime2 DATETIME,
    timestamp2 TIMESTAMP,
    date3 STRING,
    date4 BIGINT);

INSERT INTO mf_date_fun_t VALUES
(1,DATE'2021-11-29',DATETIME'2021-11-29 00:01:00',TIMESTAMP'2021-01-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-20',123456780),
(2,DATE'2021-11-28',DATETIME'2021-11-28 00:02:00',TIMESTAMP'2021-02-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-21',123456781),
(3,DATE'2021-11-27',DATETIME'2021-11-27 00:03:00',TIMESTAMP'2021-03-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-22',123456782),
(4,DATE'2021-11-26',DATETIME'2021-11-26 00:04:00',TIMESTAMP'2021-04-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-23',123456783),
(5,DATE'2021-11-25',DATETIME'2021-11-25 00:05:00',TIMESTAMP'2021-05-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-24',123456784),
(6,DATE'2021-11-24',DATETIME'2021-11-24 00:06:00',TIMESTAMP'2021-06-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-25',123456785),
(7,DATE'2021-11-23',DATETIME'2021-11-23 00:07:00',TIMESTAMP'2021-07-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-26',123456786),
(8,DATE'2021-11-22',DATETIME'2021-11-22 00:08:00',TIMESTAMP'2021-08-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-27',123456787),
(9,DATE'2021-11-21',DATETIME'2021-11-21 00:09:00',TIMESTAMP'2021-09-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-28',123456788),
(10,DATE'2021-11-20',DATETIME'2021-11-20 00:10:00',TIMESTAMP'2021-10-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-29',123456789);

Convert the STRING column date3 to DATETIME.

SELECT date3, TO_DATE(date3, 'yyyy-mm-dd') AS date3_to_date FROM mf_date_fun_t;

Result:

+------------+---------------------+
| date3      | date3_to_date       |
+------------+---------------------+
| 2021-11-20 | 2021-11-20 00:00:00 |
| 2021-11-21 | 2021-11-21 00:00:00 |
| 2021-11-22 | 2021-11-22 00:00:00 |
| 2021-11-23 | 2021-11-23 00:00:00 |
| 2021-11-24 | 2021-11-24 00:00:00 |
| 2021-11-25 | 2021-11-25 00:00:00 |
| 2021-11-26 | 2021-11-26 00:00:00 |
| 2021-11-27 | 2021-11-27 00:00:00 |
| 2021-11-28 | 2021-11-28 00:00:00 |
| 2021-11-29 | 2021-11-29 00:00:00 |
+------------+---------------------+

Related functions

TO_DATE is part of the date function suite. For more information on date calculation and conversion functions, see Date functions.