Add Update and delete support

lib/sql-parser/parser.racc

@@ -9,6 +9,8 @@ rule
   direct_sql_data_statement
     : direct_select_statement_multiple_rows
     | insert_specification
+    | update_specification
+    | delete_specification
 
   direct_select_statement_multiple_rows
     : query_expression order_by_clause { result = SQLParser::Statement::DirectSelect.new(val[0], val[1]) }
@@ -46,6 +48,22 @@ rule
     : INSERT INTO table_reference value_list { result = SQLParser::Statement::Insert.new(val[2], nil, val[3]) }
     | INSERT INTO table_reference column_list value_list { result = SQLParser::Statement::Insert.new(val[2], val[3], val[4]) }
 
+  update_specification
+    : UPDATE table_reference SET update_column_list where_clause { result = SQLParser::Statement::Update.new(val[1], val[3], val[4]) }
+
+  update_column
+    : column_name equals_operator value_expression { result = SQLParser::Statement::UpdateColumn.new(val[0], val[2]) }
+
+  update_column_sublist
+    : update_column comma update_column_sublist { result = Array(val[0]) + Array(val[2]) }
+    | update_column
+
+  update_column_list
+    : update_column_sublist { result = SQLParser::Statement::UpdateColumnList.new(val[0]) }
+
+  delete_specification
+    : DELETE from_clause where_clause { result = SQLParser::Statement::Delete.new(val[1], val[2]) }
+
   column_list
     : left_paren in_column_list right_paren { result = SQLParser::Statement::InColumnList.new(val[1]) }
 

lib/sql-parser/parser.rex

@@ -37,6 +37,8 @@ rule
 
 # keywords
             SELECT        { [:SELECT, text] }
+            UPDATE        { [:UPDATE, text] }
+            DELETE        { [:DELETE, text] }
             DATE          { [:DATE, text] }
             ASC           { [:ASC, text] }
             AS            { [:AS, text] }
@@ -74,6 +76,7 @@ rule
             DESC          { [:DESC, text] }
             CURRENT_USER  { [:CURRENT_USER, text] }
             VALUES        { [:VALUES, text] }
+            SET           { [:SET, text] }
 
 # tokens
             E             { [:E, text] }

lib/sql-parser/parser.rex.rb

@@ -45,7 +45,7 @@ def scan_file( filename )
 
   def next_token
     return if @ss.eos?
-
+    
     # skips empty actions
     until token = _next_token or @ss.eos?; end
     token
@@ -78,6 +78,12 @@ def _next_token
       when (text = @ss.scan(/SELECT/i))
          action { [:SELECT, text] }
 
+      when (text = @ss.scan(/UPDATE/i))
+         action { [:UPDATE, text] }
+
+      when (text = @ss.scan(/DELETE/i))
+         action { [:DELETE, text] }
+
       when (text = @ss.scan(/DATE/i))
          action { [:DATE, text] }
 
@@ -189,6 +195,9 @@ def _next_token
       when (text = @ss.scan(/VALUES/i))
          action { [:VALUES, text] }
 
+      when (text = @ss.scan(/SET/i))
+         action { [:SET, text] }
+
       when (text = @ss.scan(/E/i))
          action { [:E, text] }
 
@@ -260,7 +269,7 @@ def _next_token
          action { @state = nil;    [:quote, text] }
 
       when (text = @ss.scan(/.*(?=\')/i))
-         action {                 [:character_string_literal, text.gsub("''", "'")] }
+         action {                  [:character_string_literal, text.gsub("''", "'")] }
 
       else
         text = @ss.string[@ss.pos .. -1]
@@ -273,7 +282,7 @@ def _next_token
          action { @state = nil;    [:quote, text] }
 
       when (text = @ss.scan(/.*(?=\")/i))
-         action {                 [:character_string_literal, text.gsub('""', '"')] }
+         action {                  [:character_string_literal, text.gsub('""', '"')] }
 
       else
         text = @ss.string[@ss.pos .. -1]

lib/sql-parser/sql_visitor.rb

@@ -9,6 +9,29 @@ def initialize
     def visit(node)
       node.accept(self)
     end
+
+    def visit_Delete(o)
+      name = visit(o.from_clause)
+      where_clause = o.where_clause.nil? ? '' : ' ' + visit(o.where_clause)
+      "DELETE #{name}#{where_clause}"
+    end
+
+    def visit_Update(o)
+      name = visit(o.table_reference)
+      update_column_list = visit(o.update_column_list)
+      where_clause = o.where_clause.nil? ? '' : ' ' + visit(o.where_clause)
+      "UPDATE #{name} SET #{update_column_list}#{where_clause}"
+    end
+
+    def visit_UpdateColumn(o)
+      column = visit(o.column)
+      value = visit(o.value)
+      "#{column} = #{value}"
+    end
+
+    def visit_UpdateColumnList(o)
+      arrayize(o.update_columns)
+    end
 
     def visit_Insert(o)
       name = visit(o.table_reference)
@@ -359,4 +382,4 @@ def qualified_join(join_type, o)
 
   end
 
-end
+end

lib/sql-parser/statement.rb

@@ -27,6 +27,42 @@ def demodulize(str)
       end
 
     end
+
+    class Delete < Node
+
+      def initialize(from_clause, where_clause = nil)
+        @from_clause = from_clause
+        @where_clause = where_clause
+      end
+
+      attr_reader :from_clause
+      attr_reader :where_clause
+
+    end
+
+    class Update < Node
+
+      def initialize(table_reference, update_column_list, where_clause = nil)
+        @table_reference = table_reference
+        @update_column_list = update_column_list
+        @where_clause = where_clause
+      end
+
+      attr_reader :table_reference
+      attr_reader :update_column_list
+      attr_reader :where_clause
+
+    end
+
+    class UpdateColumnList < Node
+
+      def initialize(update_columns)
+        @update_columns = Array(update_columns)
+      end
+
+      attr_reader :update_columns
+
+    end
 
     class Insert < Node
 
@@ -262,17 +298,17 @@ class In < ComparisonPredicate
     class InValueList < Node
 
       def initialize(values)
-        @values = values
+        @values = Array(values)
       end
 
       attr_reader :values
 
     end
-    
+
     class InColumnList < Node
 
       def initialize(columns)
-        @columns = columns
+        @columns = Array(columns)
       end
 
       attr_reader :columns
@@ -408,6 +444,18 @@ class Table < Identifier
     class Column < Identifier
     end
 
+    class UpdateColumn < Node
+
+      def initialize(column, value)
+        @column = column
+        @value = value
+      end
+
+      attr_reader :column
+      attr_reader :value
+
+    end
+
     class As < Node
 
       def initialize(value, column)
@@ -513,4 +561,4 @@ class Integer < Literal
     end
 
   end
-end
+end

test/test_parser.rb

@@ -10,12 +10,28 @@ def test_current_user
     assert_understands 'SELECT `CURRENT_USER`'
     assert_understands 'SELECT `current_user`'
   end
+
+  def test_delete_from
+    assert_understands 'DELETE FROM `users`'
+  end
+
+  def test_delete_from_with_where
+    assert_understands 'DELETE FROM `users` WHERE `id` = 1'
+  end
+
+  def test_update
+    assert_understands 'UPDATE `users` SET `active` = 0'
+  end
+
+  def test_update_multiple
+    assert_understands 'UPDATE `users` SET `active` = 0, `email` = \'\''
+  end
 
   def test_insert_into_clause
     assert_understands 'INSERT INTO `users` VALUES (1, 2)'
   end
 
-  def test_insert_into_clause
+  def test_insert_into_clause_quoted
     assert_understands 'INSERT INTO `users` VALUES (`a`, `b`)'
   end
 

test/test_statement.rb

@@ -2,6 +2,22 @@
 require 'test/unit'
 
 class TestStatement < Test::Unit::TestCase
+  def test_update_column
+    assert_sql '`active` = 1', update_col(col('active'), int(1))
+  end
+
+  def test_update
+    assert_sql 'UPDATE `users` SET `active` = 1', SQLParser::Statement::Update.new(tbl('users'), update_col(col('active'), int(1)))
+  end
+
+  def test_delete
+    assert_sql 'DELETE FROM `users`', SQLParser::Statement::Delete.new(from(tbl('users')))
+  end
+
+  def test_insert
+    assert_sql 'INSERT INTO `users` (`id`) VALUES (1)', SQLParser::Statement::Insert.new(tbl('users'), cols(col('id')), values(int(1)))
+  end
+
   def test_direct_select
     assert_sql 'SELECT * FROM `users` ORDER BY `name`', SQLParser::Statement::DirectSelect.new(select(all, tblx(from(tbl('users')))), SQLParser::Statement::OrderBy.new(col('name')))
   end
@@ -285,10 +301,18 @@ def int(value)
     SQLParser::Statement::Integer.new(value)
   end
 
+  def values(ary)
+    SQLParser::Statement::InValueList.new(ary)
+  end
+
   def col(name)
     SQLParser::Statement::Column.new(name)
   end
 
+  def cols(ary)
+    SQLParser::Statement::InColumnList.new(ary)
+  end
+
   def tbl(name)
     SQLParser::Statement::Table.new(name)
   end
@@ -320,4 +344,8 @@ def where(search_condition)
   def group_by(columns)
     SQLParser::Statement::GroupByClause.new(columns)
   end
+
+  def update_col(column, value)
+    SQLParser::Statement::UpdateColumn.new(column, value)
+  end
 end