Support SimpleAggregateFunctions (#21)

Author: kbennoune

lib/active_record/connection_adapters/clickhouse/schema_creation.rb

@@ -45,6 +45,9 @@ def add_column_options!(sql, options)
           if options[:aggregate_function]
             sql.gsub!(/(\w+)\s+(.*)/, "\\1 AggregateFunction(#{options[:aggregate_function]}, \\2)")
           end
+          if options[:simple_aggregate_function]
+            sql.gsub!(/(\w+)\s+(.*)/, "\\1 SimpleAggregateFunction(#{options[:simple_aggregate_function]}, \\2)")
+          end
           sql.gsub!(/(\sString)\(\d+\)/, '\1')
           sql << " DEFAULT #{quote_default_expression(options[:default], options[:column])}" if options_include_default?(options)
           sql

lib/active_record/connection_adapters/clickhouse/table_definition.rb

@@ -110,7 +110,7 @@ def column(name, type, index: nil, **options)
         private
 
         def valid_column_definition_options
-          super + [:array, :low_cardinality, :fixed_string, :value, :type, :map, :codec, :unsigned, :aggregate_function]
+          super + [:array, :low_cardinality, :fixed_string, :value, :type, :map, :codec, :unsigned, :aggregate_function, :simple_aggregate_function]
         end
       end
 

lib/clickhouse-activerecord/schema_dumper.rb

@@ -177,13 +177,14 @@ def schema_low_cardinality(column)
     end
 
     def schema_aggregate_function(column)
-      match = column.sql_type.match(/AggregateFunction\((.+), (\S+)\)/)
+      match = column.sql_type.match(/((?:Simple|)AggregateFunction)\((.+), (\S+)\)/)
 
-      return {} if match.nil? || match.size != 3
+      return {} if match.nil? || match.size != 4
 
-      { aggregate_function: match[1].inspect }.tap do |spec|
-        spec[:limit] = 4 if match[2] == "Float32"
-        spec[:limit] = 8 if match[2] == "Float64"
+      type = match[1] == "AggregateFunction" ? :aggregate_function : :simple_aggregate_function
+      { type => match[2].inspect }.tap do |spec|
+        spec[:limit] = 4 if match[3] == "Float32"
+        spec[:limit] = 8 if match[3] == "Float64"
       end
     end
 

spec/fixtures/migrations/schema_table_with_aggregate_function_creation/1_create_some_table.rb

@@ -6,6 +6,7 @@ def up
       t.column :col1, "AggregateFunction(sum, Float32)", null: false
       t.column :col2, "AggregateFunction(anyLast, Float64)", null: false
       t.column :col3, "AggregateFunction(anyLast, DateTime64)", null: false
+      t.column :col4, "SimpleAggregateFunction(anyLast, DateTime64)", null: false
     end
   end
 end

spec/single/schema_dumper_spec.rb

@@ -48,6 +48,17 @@
           end
         ).to_stdout_from_any_process
       end
+
+      it 'creates a table with simple aggregate function column for an DateTime64' do
+        expect { subject }.to output(
+          satisfy do |schema|
+            expect(schema).to match(/t\.datetime "col3"/)
+            expect(schema).to match(/"col3"[^\n]+aggregate_function: "anyLast"/)
+            expect(schema).to match(/"col3"[^\n]+precision: 3/)
+            expect(schema).to match(/t\.datetime "col4", simple_aggregate_function: "anyLast"/)
+          end
+        ).to_stdout_from_any_process
+      end
     end
   end
 end