TO_DATE (Lakehouse v1)

Converts an expression to a date, including:

• Converting a timestamp-format string to a date: Extracts a date from the given string.

• Converting an integer to a date: Interprets the integer as the number of days before (for negative numbers) or after (for positive numbers) the Unix epoch (midnight on January 1, 1970). Please note that a Date value ranges from 1000-01-01 to 9999-12-31. PlaidCloud Lakehouse would return an error if you run “SELECT TO_DATE(9999999999999999999)”.

• Converting a string to a date using the specified format: The function takes two arguments, converting the first string to a date based on the format specified in the second string. To customize the date and time format in PlaidCloud Lakehouse, specifiers can be used. For a comprehensive list of supported specifiers, see Formatting Date and Time.

Date formats are expressed using the strftime specification. see the quick reference.

See also: TO_TIMESTAMP

Strftime Parameters

Quick Reference

Date

Example	Output
%m/%d/%Y	06/05/2013
%A, %B %e, %Y	Sunday, June 5, 2013
%b %e %a	Jun 5 Sun

Time

Example	Output
%H:%M	23:05
%I:%M %p	11:05 PM

Date

Symbol	Example	Area
%a	Sun	Weekday
%A	Sunday
%w	0..6 (Sunday is 0)
---	---	---
%y	13	Year
%Y	2013
---	---	---
%b	Jan	Month
%B	January
%m	01..12
---	---	---
%d	01..31	Day
%e	1..31

Time

Symbol	Example	Area
%l	1	Hour
%H	00..23	24h Hour
%I	01..12	12h Hour
—	---	---
%M	00..59	Minute
%S	00..60	Second
---	---	---
%p	AM	AM or PM
%Z	+08	Time zone
---	---	---
%j	001..366	Day of the year
%%	%	Literal % character

Analyze Syntax

func.to_date('<timestamp_expr>')
func.to_date(<integer>)
func.to_date('<string>', '<format>')

Analyze Examples

func.typeof(func.to_date('2022-01-02')), func.typeof(func.str_to_date('2022-01-02'))

┌───────────────────────────────────────────────────────────────────────────────────────┐
│ func.typeof(func.to_date('2022-01-02')) │ func.typeof(func.str_to_date('2022-01-02')) │
├─────────────────────────────────────────┼─────────────────────────────────────────────┤
│ DATE                                    │ DATE                                        │
└───────────────────────────────────────────────────────────────────────────────────────┘

SQL Syntax

-- Convert a timestamp-format string
TO_DATE('<timestamp_expr>')

-- Convert an integer
TO_DATE(<integer>)

-- Convert a string using the given format
TO_DATE('<string>', '<format>')

Aliases

• DATE
• STR_TO_DATE

Return Type

The function returns a date in the format “YYYY-MM-DD”:

SELECT TYPEOF(TO_DATE('2022-01-02')), TYPEOF(STR_TO_DATE('2022-01-02'));

┌───────────────────────────────────────────────────────────────────┐
│ typeof(to_date('2022-01-02')) │ typeof(str_to_date('2022-01-02')) │
├───────────────────────────────┼───────────────────────────────────┤
│ DATE                          │ DATE                              │
└───────────────────────────────────────────────────────────────────┘

To convert the returned date back to a string, use the DATE_FORMAT function:

SELECT DATE_FORMAT(TO_DATE('2022-01-02')) AS dt, TYPEOF(dt);

┌─────────────────────────┐
│     dt     │ typeof(dt) │
├────────────┼────────────┤
│ 2022-01-02 │ VARCHAR    │
└─────────────────────────┘

SQL Examples

SQL Examples 1: Converting a Timestamp-Format String

SELECT TO_DATE('2022-01-02T01:12:00+07:00'), STR_TO_DATE('2022-01-02T01:12:00+07:00');

┌─────────────────────────────────────────────────────────────────────────────────┐
│ to_date('2022-01-02t01:12:00+07:00') │ str_to_date('2022-01-02t01:12:00+07:00') │
├──────────────────────────────────────┼──────────────────────────────────────────┤
│ 2022-01-01                           │ 2022-01-01                               │
└─────────────────────────────────────────────────────────────────────────────────┘

SELECT TO_DATE('2022-01-02'), STR_TO_DATE('2022-01-02');

┌───────────────────────────────────────────────────┐
│ to_date('2022-01-02') │ str_to_date('2022-01-02') │
├───────────────────────┼───────────────────────────┤
│ 2022-01-02            │ 2022-01-02                │
└───────────────────────────────────────────────────┘

SQL Examples 2: Converting an Integer

SELECT TO_DATE(1), STR_TO_DATE(1), TO_DATE(-1), STR_TO_DATE(-1);

┌───────────────────────────────────────────────────────────────────┐
│ to_date(1) │ str_to_date(1) │ to_date((- 1)) │ str_to_date((- 1)) │
│    Date    │      Date      │      Date      │        Date        │
├────────────┼────────────────┼────────────────┼────────────────────┤
│ 1970-01-02 │ 1970-01-02     │ 1969-12-31     │ 1969-12-31         │
└───────────────────────────────────────────────────────────────────┘

SQL Examples 3: Converting a String Using the Given Format

SELECT TO_DATE('12/25/2022','%m/%d/%Y'), STR_TO_DATE('12/25/2022','%m/%d/%Y');

┌───────────────────────────────────────────────────────────────────────────┐
│ to_date('12/25/2022', '%m/%d/%y') │ str_to_date('12/25/2022', '%m/%d/%y') │
├───────────────────────────────────┼───────────────────────────────────────┤
│ 2022-12-25                        │ 2022-12-25                            │
└───────────────────────────────────────────────────────────────────────────┘