The TO_DATE function in Oracle can convert a string to the DATE data type. Syntax: TO_DATE(string, format_mask). format_mask is a placeholder mask that specifies the format of the date and time portion of the string. Placeholders include YYYY (year), MM (month), DD (day), HH (hour), MI (minute), SS (second), FF (billionth of a second). For example, TO_DATE('2023-03-08', 'YYYY-MM-DD') converts "2023-03-08" to DATE.
Usage of TO_DATE function in Oracle
The TO_DATE function in Oracle is used to convert strings to DATE data type.
Syntax:
TO_DATE(string, format_mask)
Where:
- string: The string to be converted.
- format_mask: Mask string specifying the string format.
Format mask:
The format mask uses the following placeholders to specify the date and time parts:
Placeholder | Description |
---|---|
YYYY |
Four-digit year |
MM |
two-digit month |
DD |
Two-digit day |
HH |
Two-digit hour (00-23) |
MI |
Two-digit minutes (00-59) |
SS |
Two-digit seconds (00-59) |
FF |
billionth of a second |
Example:
- Convert "2023-03-08" string to DATE:
TO_DATE('2023-03-08', 'YYYY-MM-DD')
- Convert the string "2023-03-08 14:30:15" to DATE:
TO_DATE('2023-03-08 14:30:15', 'YYYY-MM-DD HH24:MI:SS')
- Convert the string "08/03/2023 02:30 PM" to DATE:
TO_DATE('08/03/2023 02:30 PM', 'MM/DD/YYYY HH:MI PM')
Note:
- The format mask must match the format of the string, otherwise an error will occur.
- TO_DATE function returns NULL if the string cannot be converted to the DATE data type.
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