PostgreSQL – TO_TIMESTAMP Function
In PostgreSQL, the TO_TIMESTAMP
function is used to convert a string representation of a timestamp into a timestamp data type. It allows you to parse timestamp strings in a specific format and convert them into valid timestamp values that can be stored or used for date and time-related operations.
The basic syntax of the TO_TIMESTAMP
function is as follows:
TO_TIMESTAMP(timestamp_string, format);
where timestamp_string
is the string representing the timestamp that you want to convert,
and format
is the format pattern that matches the structure of the timestamp_string
.
Below is an example of using the TO_TIMESTAMP
function to convert a timestamp string into a timestamp:
SELECT TO_TIMESTAMP('2023-08-06 15:30:45', 'YYYY-MM-DD HH24:MI:SS') AS converted_timestamp;
This query will return 2023-08-06 15:30:45
as a timestamp data type, assuming the timestamp string ‘2023-08-06 15:30:45’ is in the format ‘YYYY-MM-DD HH24:MI:SS’.
The format pattern consists of special placeholders that represent the parts of the timestamp
where YYYY
is the Four-digit year.
MM
: Two-digit month (01 to 12).
DD
: Two-digit day of the month (01 to 31).
HH24
: Two-digit hour in 24-hour format (00 to 23).
MI
: Two-digit minutes (00 to 59).
SS
: Two-digit seconds (00 to 59).
For instance, if the timestamp string is in the format ‘DD-MM-YYYY HH:MI:SS’, you would use the following TO_TIMESTAMP
statement:
SELECT TO_TIMESTAMP('06-08-2023 15:30:45', 'DD-MM-YYYY HH:MI:SS') AS converted_timestamp;
This would correctly convert the timestamp string ’06-08-2023 15:30:45′ to 2023-08-06 15:30:45
.
It’s important to ensure that the timestamp_string
matches the format specified in the TO_TIMESTAMP
function. If the timestamp string and format do not align correctly, PostgreSQL will raise an error.
The TO_TIMESTAMP
function is useful when dealing with timestamp values stored as strings or when importing data from external sources with timestamp information in non-standard formats. It allows you to convert these strings into valid timestamps and store them in timestamp columns within your PostgreSQL database.