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Update docs/en/sql-reference/functions/array-functions.md

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Co-authored-by: olgarev <56617294+olgarev@users.noreply.github.com>
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docs/en/sql-reference/functions/array-functions.md
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@ -18,7 +18,7 @@ empty([x])
An array is considered empty if it contains all empty elements.
!!! note "Note"
Can be optimized by enabling the [optimize_functions_to_subcolumns](../../operations/settings/settings.md#optimize-functions-to-subcolumns) setting. With `optimize_functions_to_subcolumns = 1` the function reads only [size0](../../sql-reference/data-types/array.md#array-size) subcolumn instead of reading and processing the whole array column. The query `SELECT empty(arr) FROM table;` transforms to `SELECT arr.size0 = 0 FROM TABLE;`.
Can be optimized by enabling the [optimize_functions_to_subcolumns](../../operations/settings/settings.md#optimize-functions-to-subcolumns) setting. With `optimize_functions_to_subcolumns = 1` the function reads only [size0](../../sql-reference/data-types/array.md#array-size) subcolumn instead of reading and processing the whole array. The query `SELECT empty(arr) FROM table;` transforms to `SELECT arr.size0 = 0 FROM table;`.
The function also works for [strings](string-functions.md#empty) or [UUID](uuid-functions.md#empty).