--- description: Scalar functions for regular expressions title: Regex functions image: https://developers.cloudflare.com/basin-pipelines/sql-reference/scalar-functions/regex/og.png?v=55440386e38f0300 --- [Skip to content](#main-content) > Documentation Index > Fetch the complete documentation index at: https://developers.cloudflare.com/basin-pipelines/llms.txt > Use this file to discover all available pages before exploring further. # Regex functions Last updated Oct 1, 2026|Copy as Markdown| [View as Markdown](https://developers.cloudflare.com/basin-pipelines/sql-reference/scalar-functions/regex/index.md)| [Agent setup](https://developers.cloudflare.com/agent-setup/) *Basin Pipelines scalar function implementations are based on [Apache DataFusion ↗︎](https://arrow.apache.org/datafusion/) (via [Arroyo ↗︎](https://www.arroyo.dev/)) and these docs are derived from the DataFusion function reference.* Basin Pipelines uses a [PCRE-like ↗︎](https://en.wikibooks.org/wiki/Regular_Expressions/Perl-Compatible_Regular_Expressions) regular expression [syntax ↗︎](https://docs.rs/regex/latest/regex/#syntax) (minus support for several features including look-around and backreferences). ## `regexp_like` Returns true if a [regular expression ↗︎](https://docs.rs/regex/latest/regex/#syntax) has at least one match in a string, false otherwise. ```plaintext regexp_like(str, regexp[, flags]) ``` **Arguments** - **str**: String expression to operate on. Can be a constant, column, or function, and any combination of string operators. - **regexp**: Regular expression to test against the string expression. Can be a constant, column, or function. - **flags**: Optional regular expression flags that control the behavior of the regular expression. The following flags are supported: - **i**: case-insensitive: letters match both upper and lower case - **m**: multi-line mode: ^ and $ match begin/end of line - **s**: allow . to match \\n - **R**: enables CRLF mode: when multi-line mode is enabled, \\r\\n is used - **U**: swap the meaning of x\* and x\*? **Example** ```sql select regexp_like('Köln', '[a-zA-Z]ö[a-zA-Z]{2}'); +--------------------------------------------------------+ | regexp_like(Utf8("Köln"),Utf8("[a-zA-Z]ö[a-zA-Z]{2}")) | +--------------------------------------------------------+ | true | +--------------------------------------------------------+ SELECT regexp_like('aBc', '(b|d)', 'i'); +--------------------------------------------------+ | regexp_like(Utf8("aBc"),Utf8("(b|d)"),Utf8("i")) | +--------------------------------------------------+ | true | +--------------------------------------------------+ ``` Additional examples can be found [here ↗︎](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/regexp.rs) ## `regexp_match` Returns a list of [regular expression ↗︎](https://docs.rs/regex/latest/regex/#syntax) matches in a string. ```plaintext regexp_match(str, regexp[, flags]) ``` **Arguments** - **str**: String expression to operate on. Can be a constant, column, or function, and any combination of string operators. - **regexp**: Regular expression to match against. Can be a constant, column, or function. - **flags**: Optional regular expression flags that control the behavior of the regular expression. The following flags are supported: - **i**: case-insensitive: letters match both upper and lower case - **m**: multi-line mode: ^ and $ match begin/end of line - **s**: allow . to match \\n - **R**: enables CRLF mode: when multi-line mode is enabled, \\r\\n is used - **U**: swap the meaning of x\* and x\*? **Example** ```sql select regexp_match('Köln', '[a-zA-Z]ö[a-zA-Z]{2}'); +---------------------------------------------------------+ | regexp_match(Utf8("Köln"),Utf8("[a-zA-Z]ö[a-zA-Z]{2}")) | +---------------------------------------------------------+ | [Köln] | +---------------------------------------------------------+ SELECT regexp_match('aBc', '(b|d)', 'i'); +---------------------------------------------------+ | regexp_match(Utf8("aBc"),Utf8("(b|d)"),Utf8("i")) | +---------------------------------------------------+ | [B] | +---------------------------------------------------+ ``` Additional examples can be found [here ↗︎](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/regexp.rs) ## `regexp_replace` Replaces substrings in a string that match a [regular expression ↗︎](https://docs.rs/regex/latest/regex/#syntax). ```plaintext regexp_replace(str, regexp, replacement[, flags]) ``` **Arguments** - **str**: String expression to operate on. Can be a constant, column, or function, and any combination of string operators. - **regexp**: Regular expression to match against. Can be a constant, column, or function. - **replacement**: Replacement string expression. Can be a constant, column, or function, and any combination of string operators. - **flags**: Optional regular expression flags that control the behavior of the regular expression. The following flags are supported: - **g**: (global) Search globally and do not return after the first match - **i**: case-insensitive: letters match both upper and lower case - **m**: multi-line mode: ^ and $ match begin/end of line - **s**: allow . to match \\n - **R**: enables CRLF mode: when multi-line mode is enabled, \\r\\n is used - **U**: swap the meaning of x\* and x\*? **Example** ```sql SELECT regexp_replace('foobarbaz', 'b(..)', 'X\\1Y', 'g'); +------------------------------------------------------------------------+ | regexp_replace(Utf8("foobarbaz"),Utf8("b(..)"),Utf8("X\1Y"),Utf8("g")) | +------------------------------------------------------------------------+ | fooXarYXazY | +------------------------------------------------------------------------+ SELECT regexp_replace('aBc', '(b|d)', 'Ab\\1a', 'i'); +-------------------------------------------------------------------+ | regexp_replace(Utf8("aBc"),Utf8("(b|d)"),Utf8("Ab\1a"),Utf8("i")) | +-------------------------------------------------------------------+ | aAbBac | +-------------------------------------------------------------------+ ``` Additional examples can be found [here ↗︎](https://github.com/apache/datafusion/blob/main/datafusion-examples/examples/regexp.rs) ## `position` Returns the position of `substr` in `origstr` (counting from 1). If `substr` does not appear in `origstr`, return 0. ```plaintext position(substr in origstr) ``` **Arguments** - **substr**: The pattern string. - **origstr**: The model string. Was this helpful? YesNo ## On this page [![](https://developers.cloudflare.com/_astro/logo.te5VL_aD.svg)Docs](https://developers.cloudflare.com/) ```json {"@context":"https://schema.org","@type":"TechArticle","@id":"https://developers.cloudflare.com/basin-pipelines/sql-reference/scalar-functions/regex/#page","headline":"Regex functions","description":"Scalar functions for regular expressions","url":"https://developers.cloudflare.com/basin-pipelines/sql-reference/scalar-functions/regex/","inLanguage":"en","image":"https://developers.cloudflare.com/basin-pipelines/sql-reference/scalar-functions/regex/og.png?v=55440386e38f0300","dateModified":"2026-10-01","publisher":{"@type":"Organization","name":"Cloudflare","description":"One platform for your apps, agents, and workforce. 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