ClickHouse/docs/en/functions/splitting_merging_functions.rst

Functions for splitting and merging strings and arrays
----------------

splitByChar(separator, s)
~~~~~~~~~~~~
Splits a string into substrings, using 'separator' as the separator.
'separator' must be a string constant consisting of exactly one character.
Returns an array of selected substrings. Empty substrings may be selected if the separator occurs at the beginning or end of the string, or if there are multiple consecutive separators.

splitByString(separator, s)
~~~~~~~~~~~
The same as above, but it uses a string of multiple characters as the separator. The string must be non-empty.

arrayStringConcat(arr[, separator])
~~~~~~~~~~~~~
Concatenates strings from the array elements, using 'separator' as the separator.
'separator' is a string constant, an optional parameter. By default it is an empty string.
Returns a string.

alphaTokens(s)
~~~~~~~~~~
Selects substrings of consecutive bytes from the range a-z and A-Z.
Returns an array of selected substrings.