`SELECT ... WHERE match(key, '^prefix...')`
should use index similarly to
`SELECT ... WHERE key LIKE 'prefix%'`
function->arguments->children = std::move(filters);
            filter_query = function;
        }
        /** When non-strictly monotonic functions are employed in functional index (e.g. ORDER BY toStartOfHour(dateTime)),
          * the use of NOT operator in predicate will result in the indexing algorithm leave out some data.
          * This is caused by rewriting in KeyCondition::tryParseAtomFromAST of relational operators to less strict
          * when parsing the AST into internal RPN representation.
          * To overcome the problem, before parsing the AST we transform it to its semantically equivalent form where all NOT's
          * are pushed down and applied (when possible) to leaf nodes.
          */
        auto ast = cloneASTWithInversionPushDown(filter_query);
        traverseAST(Tree(ast.get()), context, block_with_constants);
    }
    else
    {
        rpn.emplace_back(RPNElement::FUNCTION_UNKNOWN);
    }
}
KeyCondition::KeyCondition(
    ActionDAGNodes dag_nodes,
    TreeRewriterResultPtr syntax_analyzer_result,
    PreparedSetsPtr prepared_sets_,
    ContextPtr context,
    const Names & key_column_names,
    const ExpressionActionsPtr & key_expr_,
    bool single_point_,
    bool strict_)
    : key_expr(key_expr_)
    , key_subexpr_names(getAllSubexpressionNames(*key_expr))
    , prepared_sets(prepared_sets_)