regexp_replace
1. REGEXP_REPLACE Function
=======regexp_replace
1. REGEXP_REPLACE Function
>>>>>>> 9d19b1c8cb744c8e86d5c15b74d8b5f719ad62beThe REGEXP_REPLACE function in H2 database is used to replace substrings in a string that match a specified regular expression pattern.
2. Syntax
The syntax for the REGEXP_REPLACE function in H2 database is as follows:
REGEXP_REPLACE(input_string, pattern, replacement)
Arguments
input_string
: The string in which the replacement needs to be performed.pattern
: The regular expression pattern to be matched.replacement
: The string to replace the matched pattern.
Return
- The REGEXP_REPLACE function returns the modified string after replacing the matching substrings.
3. Notes
- The REGEXP_REPLACE function in H2 database uses regular expressions to find and replace substrings. Make sure you are familiar with regular expression syntax.
- If the input string or pattern is
NULL
, the function will returnNULL
. - By default, the function replaces all occurrences of the pattern in the input string. To replace only the first occurrence, you can use the optional
occurrence
parameter. - The REGEXP_REPLACE function is case-sensitive. To perform a case-insensitive replacement, you can use the
(?i)
flag in the pattern.
4. Examples
Here are a few examples demonstrating the usage of the REGEXP_REPLACE function in H2 database:
Example 1 - Replacing all occurrences of a pattern in a string:
SELECT REGEXP_REPLACE('Hello World', 'o', 'x') AS replaced_string;
Output:
replaced_string
---------------
Hellx Wxrld
Example 2 - Replacing the first occurrence of a pattern in a string:
SELECT REGEXP_REPLACE('Hello World', 'o', 'x', 1) AS replaced_string;
Output:
replaced_string
---------------
Hellx World
Example 3 - Performing a case-insensitive replacement:
SELECT REGEXP_REPLACE('Hello World', '(?i)o', 'x') AS replaced_string;
Output:
replaced_string
---------------
Hellx Wxrld
5. Related Functions
- regexp_like - Check if a string matches a regular expression pattern.
- REGEXP_INSTR - Find the position of a regular expression pattern in a string.
- REGEXP_SUBSTRING - Extract substrings from a string based on a regular expression pattern.