Functions for Searching in Strings

All functions in this section search case-sensitively by default. Case-insensitive search is usually provided by separate function variants.

:::note Case-insensitive search follows the lowercase-uppercase rules of the English language. E.g. Uppercased i in the English language is I whereas in the Turkish language it is İ - results for languages other than English may be unexpected. :::

Functions in this section also assume that the searched string (referred to in this section as haystack) and the search string (referred to in this section as needle) are single-byte encoded text. If this assumption is violated, no exception is thrown and results are undefined. Search with UTF-8 encoded strings is usually provided by separate function variants. Likewise, if a UTF-8 function variant is used and the input strings are not UTF-8 encoded text, no exception is thrown and the results are undefined. Note that no automatic Unicode normalization is performed, however you can use the normalizeUTF8*() functions for that.

General strings functions and functions for replacing in strings are described separately.

:::note The documentation below is generated from the system.functions system table. :::

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