The CONVERT function converts a value in Oracle from one data type to another, and its syntax is CONVERT(
, ). It can be used to convert string to number, number to string, date to string, string to date, binary to string and string to binary.
Usage of CONVERT function in Oracle
The CONVERT function is used in Oracle to convert data types. It converts a value from one data type to another.
Syntax
<code>CONVERT(, )</code>
Parameters
- ##
: The data type to convert to. - : The value to be converted.
Usage
The CONVERT function can be used to convert various data types, including:- String to number
- Number to string
- Date to string
- String to date
- Binary to string
- String to binary
Example
Convert string to number:<code>SELECT CONVERT(NUMBER, '123.45') FROM DUAL;</code>Convert number to string:
<code>SELECT CONVERT(VARCHAR2(20), 12345) FROM DUAL;</code>Convert date For string:
<code>SELECT CONVERT(CHAR(10), SYSDATE, 'YYYY-MM-DD') FROM DUAL;</code>Convert string to date:
<code>SELECT CONVERT(DATE, '2023-03-08', 'YYYY-MM-DD') FROM DUAL;</code>Convert binary to string:
<code>SELECT CONVERT(VARCHAR2(100), DUMP(NULL, 16)) FROM DUAL;</code>Convert string to binary:
<code>SELECT CONVERT(BLOB, 'This is a string.') FROM DUAL;</code>
Notes
- Data type restrictions: Both the value to be converted and the target data type must be supported by Oracle.
- Format string: When converting dates or strings, a format string can be specified to control the output format.
- Default format: If you do not specify a format string, Oracle's default format will be used.
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