oracle regexp

Oracle Regular Expression (RegEx) is a powerful tool used to search, match and manipulate text based on patterns. It is used in Oracle databases for a variety of tasks such as data validation, text search, and string manipulation.

The syntax for Oracle RegEx is similar to other programming languages that use RegEx. Some common RegEx functions in Oracle include REGEXP_LIKE, REGEXP_REPLACE, and REGEXP_INSTR. These functions allow you to search and manipulate text based on patterns such as character classes, quantifiers, and anchors.

For example, the REGEXP_LIKE function can be used to search for a pattern in a string. The syntax for this function is:

REGEXP_LIKE(string, pattern)

Where `string` is the input string and `pattern` is the RegEx pattern to search for.

Here is an example of using REGEXP_LIKE to search for a pattern in a string:

SELECT *
FROM my_table
WHERE REGEXP_LIKE(my_column, '^[A-Za-z]+$');

This query will return all rows from `my_table` where the value in `my_column` contains only letters (uppercase or lowercase).

There are many other RegEx functions available in Oracle, each with its own syntax and usage. Mastering Oracle RegEx can be a powerful tool for anyone working with text data in an Oracle database.