Updated extractAllGroupsHorizontal - flexible limit on number of matches per row.

If it is not set via third argument, it deafults to previously hardcoded
value 1000.

src/Functions/extractAllGroups.h

@@ -55,7 +55,8 @@ public:
 
     String getName() const override { return name; }
 
-    size_t getNumberOfArguments() const override { return 2; }
+    size_t getNumberOfArguments() const override { return Kind == ExtractAllGroupsResultKind::HORIZONTAL ? 0 : 2; }
+    bool isVariadic() const override { return Kind == ExtractAllGroupsResultKind::HORIZONTAL; }
 
     bool useDefaultImplementationForConstants() const override { return true; }
     ColumnNumbers getArgumentsThatAreAlwaysConstant() const override { return {1}; }
@@ -66,7 +67,13 @@ public:
             {"haystack", isStringOrFixedString, nullptr, "const String or const FixedString"},
             {"needle", isStringOrFixedString, isColumnConst, "const String or const FixedString"},
         };
-        validateFunctionArgumentTypes(*this, arguments, args);
+        FunctionArgumentDescriptors optional_args;
+        if constexpr (Kind == ExtractAllGroupsResultKind::HORIZONTAL)
+        {
+            optional_args.push_back(FunctionArgumentDescriptor{"max_matches_per_row", isUnsignedInteger, isColumnConst, "const Unsigned Int"});
+        }
+
+        validateFunctionArgumentTypes(*this, arguments, args, optional_args);
 
         /// Two-dimensional array of strings, each `row` of top array represents matching groups.
         return std::make_shared<DataTypeArray>(std::make_shared<DataTypeArray>(std::make_shared<DataTypeString>()));
@@ -147,6 +154,10 @@ public:
         }
         else
         {
+            /// Additional limit to fail fast on supposedly incorrect usage, arbitrary value.
+            static constexpr size_t MAX_MATCHES_PER_ROW = 1000;
+            const auto max_matches_per_row = arguments.size() >= 3 ? arguments[2].column->getUInt(0) : MAX_MATCHES_PER_ROW;
+
             PODArray<StringPiece, 0> all_matches;
             /// Number of times RE matched on each row of haystack column.
             PODArray<size_t, 0> number_of_matches_per_row;
@@ -172,16 +183,13 @@ public:
                     for (size_t group = 1; group <= groups_count; ++group)
                         all_matches.push_back(matched_groups[group]);
 
-                    /// Additional limit to fail fast on supposedly incorrect usage, arbitrary value.
+                    ++matches_per_row;
-                    static constexpr size_t MAX_MATCHES_PER_ROW = 1000;
+                    if (matches_per_row > max_matches_per_row)
-                    if (matches_per_row > MAX_MATCHES_PER_ROW)
                         throw Exception(ErrorCodes::TOO_LARGE_ARRAY_SIZE,
                                 "Too many matches per row (> {}) in the result of function {}",
-                                MAX_MATCHES_PER_ROW, getName());
+                                max_matches_per_row, getName());
 
                     pos = matched_groups[0].data() + std::max<size_t>(1, matched_groups[0].size());
-
-                    ++matches_per_row;
                 }
 
                 number_of_matches_per_row.push_back(matches_per_row);

tests/queries/0_stateless/01246_extractAllGroupsHorizontal.reference

@@ -1,4 +1,3 @@
-0 groups, zero matches
 1 group, multiple matches, String and FixedString
 [['hello','world']]
 [['hello','world']]

tests/queries/0_stateless/01246_extractAllGroupsHorizontal.sql

@@ -5,9 +5,13 @@ SELECT extractAllGroupsHorizontal('hello', 123);  --{serverError 43} invalid arg
 SELECT extractAllGroupsHorizontal(123, 'world');  --{serverError 43}  invalid argument type
 SELECT extractAllGroupsHorizontal('hello world', '((('); --{serverError 427}  invalid re
 SELECT extractAllGroupsHorizontal('hello world', materialize('\\w+')); --{serverError 44} non-cons needle
+SELECT extractAllGroupsHorizontal('hello world', '(\\w+)', 'foobar'); --{serverError 43} invalid argument type
+SELECT extractAllGroupsHorizontal('hello world', '(\\w+)', materialize(10)); --{serverError 44} non-const max_matches_per_row
+SELECT extractAllGroupsHorizontal('hello world', '\\w+');  -- { serverError 36 } 0 groups
+SELECT extractAllGroupsHorizontal('hello world', '(\\w+)', 0);  -- { serverError 128 } to many groups matched per row
+SELECT extractAllGroupsHorizontal('hello world', '(\\w+)', 1);  -- { serverError 128 } to many groups matched per row
 
-SELECT '0 groups, zero matches';
+SELECT extractAllGroupsHorizontal('hello world', '(\\w+)', 1000000000) FORMAT Null; -- users now can set limit bigger than previous 1000 matches per row
-SELECT extractAllGroupsHorizontal('hello world', '\\w+');  -- { serverError 36 }
 
 SELECT '1 group, multiple matches, String and FixedString';
 SELECT extractAllGroupsHorizontal('hello world', '(\\w+)');

tests/queries/0_stateless/01246_extractAllGroupsVertical.reference

@@ -1,4 +1,3 @@
-0 groups, zero matches
 1 group, multiple matches, String and FixedString
 [['hello'],['world']]
 [['hello'],['world']]

tests/queries/0_stateless/01246_extractAllGroupsVertical.sql

@@ -5,9 +5,8 @@ SELECT extractAllGroupsVertical('hello', 123);  --{serverError 43} invalid argum
 SELECT extractAllGroupsVertical(123, 'world');  --{serverError 43}  invalid argument type
 SELECT extractAllGroupsVertical('hello world', '((('); --{serverError 427}  invalid re
 SELECT extractAllGroupsVertical('hello world', materialize('\\w+')); --{serverError 44} non-const needle
-
+SELECT extractAllGroupsVertical('hello world', '(\\w+)', 123); --{serverError 42} only 2 arguments
-SELECT '0 groups, zero matches';
+SELECT extractAllGroupsVertical('hello world', '\\w+'); -- { serverError 36 } 0 groups
-SELECT extractAllGroupsVertical('hello world', '\\w+'); -- { serverError 36 }
 
 SELECT '1 group, multiple matches, String and FixedString';
 SELECT extractAllGroupsVertical('hello world', '(\\w+)');