diff options
Diffstat (limited to 'lib/sql_algebra')
19 files changed, 230 insertions, 9 deletions
diff --git a/lib/sql_algebra/predicates/binary_predicate.rb b/lib/sql_algebra/predicates/binary_predicate.rb index 3e5b9ce193..9463f162c5 100644 --- a/lib/sql_algebra/predicates/binary_predicate.rb +++ b/lib/sql_algebra/predicates/binary_predicate.rb @@ -12,7 +12,10 @@ class BinaryPredicate < Predicate def to_sql(builder = ConditionsBuilder.new) builder.call do - send(predicate_name, attribute1.to_sql(self), attribute2.to_sql(self)) + send(predicate_name) do + attribute1.to_sql(self) + attribute2.to_sql(self) + end end end end
\ No newline at end of file diff --git a/lib/sql_algebra/relations/attribute.rb b/lib/sql_algebra/relations/attribute.rb index af448286f1..85d40dfb12 100644 --- a/lib/sql_algebra/relations/attribute.rb +++ b/lib/sql_algebra/relations/attribute.rb @@ -1,8 +1,8 @@ class Attribute - attr_reader :relation, :attribute_name + attr_reader :relation, :attribute_name, :aliaz - def initialize(relation, attribute_name) - @relation, @attribute_name = relation, attribute_name + def initialize(relation, attribute_name, aliaz = nil) + @relation, @attribute_name, @aliaz = relation, attribute_name, aliaz end def eql?(other) @@ -33,7 +33,9 @@ class Attribute MatchPredicate.new(self, regexp) end - def to_sql(ignore_builder_because_i_can_only_exist_atomically = nil) - ColumnBuilder.new(relation.table, attribute_name) + def to_sql(builder = SelectsBuilder.new) + builder.call do + column relation.table, attribute_name, aliaz + end end end
\ No newline at end of file diff --git a/lib/sql_algebra/relations/inner_join_operation.rb b/lib/sql_algebra/relations/inner_join_operation.rb new file mode 100644 index 0000000000..6b5c5ce8d0 --- /dev/null +++ b/lib/sql_algebra/relations/inner_join_operation.rb @@ -0,0 +1,6 @@ +class InnerJoinOperation < JoinOperation + protected + def relation_class + InnerJoinRelation + end +end
\ No newline at end of file diff --git a/lib/sql_algebra/relations/inner_join_relation.rb b/lib/sql_algebra/relations/inner_join_relation.rb new file mode 100644 index 0000000000..1ef965a6f5 --- /dev/null +++ b/lib/sql_algebra/relations/inner_join_relation.rb @@ -0,0 +1,5 @@ +class InnerJoinRelation < JoinRelation + def join_name + :inner_join + end +end
\ No newline at end of file diff --git a/lib/sql_algebra/relations/left_outer_join_operation.rb b/lib/sql_algebra/relations/left_outer_join_operation.rb new file mode 100644 index 0000000000..fbb2a4e2ed --- /dev/null +++ b/lib/sql_algebra/relations/left_outer_join_operation.rb @@ -0,0 +1,6 @@ +class LeftOuterJoinOperation < JoinOperation + protected + def relation_class + LeftOuterJoinRelation + end +end
\ No newline at end of file diff --git a/lib/sql_algebra/relations/left_outer_join_relation.rb b/lib/sql_algebra/relations/left_outer_join_relation.rb new file mode 100644 index 0000000000..c7722c394d --- /dev/null +++ b/lib/sql_algebra/relations/left_outer_join_relation.rb @@ -0,0 +1,5 @@ +class LeftOuterJoinRelation < JoinRelation + def join_name + :left_outer_join + end +end
\ No newline at end of file diff --git a/lib/sql_algebra/relations/order_relation.rb b/lib/sql_algebra/relations/order_relation.rb index e3c29dcc27..384a007bc2 100644 --- a/lib/sql_algebra/relations/order_relation.rb +++ b/lib/sql_algebra/relations/order_relation.rb @@ -12,7 +12,9 @@ class OrderRelation < Relation def to_sql(builder = SelectBuilder.new) relation.to_sql(builder).call do attributes.each do |attribute| - order_by attribute.to_sql(self) + order_by do + attribute.to_sql(self) + end end end end diff --git a/lib/sql_algebra/relations/projection_relation.rb b/lib/sql_algebra/relations/projection_relation.rb index ca5f0bfca4..0b5d645d79 100644 --- a/lib/sql_algebra/relations/projection_relation.rb +++ b/lib/sql_algebra/relations/projection_relation.rb @@ -11,7 +11,9 @@ class ProjectionRelation < Relation def to_sql(builder = SelectBuilder.new) relation.to_sql(builder).call do - select attributes.collect { |a| a.to_sql(self) } + select do + attributes.collect { |a| a.to_sql(self) } + end end end end
\ No newline at end of file diff --git a/lib/sql_algebra/relations/selection_relation.rb b/lib/sql_algebra/relations/selection_relation.rb index cce93917c4..51461de7d2 100644 --- a/lib/sql_algebra/relations/selection_relation.rb +++ b/lib/sql_algebra/relations/selection_relation.rb @@ -17,4 +17,6 @@ class SelectionRelation < Relation end end end + + delegate :[], :to => :relation end
\ No newline at end of file diff --git a/lib/sql_algebra/relations/table_relation.rb b/lib/sql_algebra/relations/table_relation.rb index eee24e5d68..60bdfda8ee 100644 --- a/lib/sql_algebra/relations/table_relation.rb +++ b/lib/sql_algebra/relations/table_relation.rb @@ -7,7 +7,7 @@ class TableRelation < Relation def to_sql(builder = SelectBuilder.new) builder.call do - select :* + select { all } from table end end diff --git a/lib/sql_algebra/sql_builder/conditions_builder.rb b/lib/sql_algebra/sql_builder/conditions_builder.rb new file mode 100644 index 0000000000..5d42a36cec --- /dev/null +++ b/lib/sql_algebra/sql_builder/conditions_builder.rb @@ -0,0 +1,16 @@ +class ConditionsBuilder < SqlBuilder + def initialize(&block) + @conditions = [] + super(&block) + end + + def equals(&block) + @conditions << EqualsConditionBuilder.new(&block) + end + + def to_s + @conditions.join(' AND ') + end + + delegate :blank?, :to => :@conditions +end
\ No newline at end of file diff --git a/lib/sql_algebra/sql_builder/equals_condition_builder.rb b/lib/sql_algebra/sql_builder/equals_condition_builder.rb new file mode 100644 index 0000000000..016395556a --- /dev/null +++ b/lib/sql_algebra/sql_builder/equals_condition_builder.rb @@ -0,0 +1,18 @@ +class EqualsConditionBuilder < SqlBuilder + def initialize(&block) + @operands = [] + super(&block) + end + + def column(table, column, aliaz = nil) + @operands << (aliaz ? aliaz : "#{table}.#{column}") + end + + def value(value) + @operands << value + end + + def to_s + "#{@operands[0]} = #{@operands[1]}" + end +end
\ No newline at end of file diff --git a/lib/sql_algebra/sql_builder/inner_join_builder.rb b/lib/sql_algebra/sql_builder/inner_join_builder.rb new file mode 100644 index 0000000000..6aec703325 --- /dev/null +++ b/lib/sql_algebra/sql_builder/inner_join_builder.rb @@ -0,0 +1,5 @@ +class InnerJoinBuilder < JoinBuilder + def join_type + "INNER JOIN" + end +end
\ No newline at end of file diff --git a/lib/sql_algebra/sql_builder/join_builder.rb b/lib/sql_algebra/sql_builder/join_builder.rb new file mode 100644 index 0000000000..28f4437dec --- /dev/null +++ b/lib/sql_algebra/sql_builder/join_builder.rb @@ -0,0 +1,13 @@ +class JoinBuilder < SqlBuilder + def initialize(table, &block) + @table = table + @conditions = ConditionsBuilder.new + super(&block) + end + + delegate :call, :to => :@conditions + + def to_s + "#{join_type} #{@table} ON #{@conditions}" + end +end
\ No newline at end of file diff --git a/lib/sql_algebra/sql_builder/joins_builder.rb b/lib/sql_algebra/sql_builder/joins_builder.rb new file mode 100644 index 0000000000..36a92e9922 --- /dev/null +++ b/lib/sql_algebra/sql_builder/joins_builder.rb @@ -0,0 +1,18 @@ +class JoinsBuilder < SqlBuilder + def initialize(&block) + @joins = [] + super(&block) + end + + def inner_join(table, &block) + @joins << InnerJoinBuilder.new(table, &block) + end + + def left_outer_join(table, &block) + @joins << LeftOuterJoinBuilder.new(table, &block) + end + + def to_s + @joins.join(' ') + end +end
\ No newline at end of file diff --git a/lib/sql_algebra/sql_builder/left_outer_join_builder.rb b/lib/sql_algebra/sql_builder/left_outer_join_builder.rb new file mode 100644 index 0000000000..dad3f85810 --- /dev/null +++ b/lib/sql_algebra/sql_builder/left_outer_join_builder.rb @@ -0,0 +1,5 @@ +class LeftOuterJoinBuilder < JoinBuilder + def join_type + "LEFT OUTER JOIN" + end +end
\ No newline at end of file diff --git a/lib/sql_algebra/sql_builder/select_builder.rb b/lib/sql_algebra/sql_builder/select_builder.rb new file mode 100644 index 0000000000..d4eb4feb56 --- /dev/null +++ b/lib/sql_algebra/sql_builder/select_builder.rb @@ -0,0 +1,63 @@ +class SelectBuilder < SqlBuilder + def select(&block) + @selects = SelectsBuilder.new(&block) + end + + def from(table, &block) + @table = table + @joins = JoinsBuilder.new(&block) + end + delegate :inner_join, :left_outer_join, :to => :@joins + + def where(&block) + @conditions ||= ConditionsBuilder.new + @conditions.call(&block) + end + + def order_by(&block) + @orders = OrderBuilder.new(&block) + end + + def limit(i, offset = nil) + @limit = i + offset(offset) if offset + end + + def offset(i) + @offset = i + end + + def to_s + [select_clause, + from_clause, + where_clause, + order_by_clause, + limit_clause, + offset_clause].compact.join("\n") + end + + private + def select_clause + "SELECT #{@selects}" unless @selects.blank? + end + + def from_clause + "FROM #{@table} #{@joins}" unless @table.blank? + end + + def where_clause + "WHERE #{@conditions}" unless @conditions.blank? + end + + def order_by_clause + "ORDER BY #{@orders}" unless @orders.blank? + end + + def limit_clause + "LIMIT #{@limit}" unless @limit.blank? + end + + def offset_clause + "OFFSET #{@offset}" unless @offset.blank? + end +end
\ No newline at end of file diff --git a/lib/sql_algebra/sql_builder/sql_builder.rb b/lib/sql_algebra/sql_builder/sql_builder.rb new file mode 100644 index 0000000000..5cfbe578d5 --- /dev/null +++ b/lib/sql_algebra/sql_builder/sql_builder.rb @@ -0,0 +1,28 @@ +class SqlBuilder + def initialize(&block) + @callers = [] + call(&block) if block + end + + def method_missing(method, *args) + @callers.last.send(method, *args) + end + + def ==(other) + to_s == other.to_s + end + + def to_s + end + + def call(&block) + returning self do |builder| + @callers << eval("self", block.binding) + begin + instance_eval &block + ensure + @callers.pop + end + end + end +end
\ No newline at end of file diff --git a/lib/sql_algebra/sql_builder/sql_builder_adapter.rb b/lib/sql_algebra/sql_builder/sql_builder_adapter.rb new file mode 100644 index 0000000000..9bb5271f33 --- /dev/null +++ b/lib/sql_algebra/sql_builder/sql_builder_adapter.rb @@ -0,0 +1,22 @@ +class SqlBuilderAdapter + instance_methods.each { |m| undef_method m unless m =~ /^__|^instance_eval|class/ } + + def initialize(adaptee, &block) + @adaptee = adaptee + (class << self; self end).class_eval do + (adaptee.methods - instance_methods).each { |m| delegate m, :to => :@adaptee } + end + (class << self; self end).instance_exec(@adaptee, &block) + end + + def call(&block) + @caller = eval("self", block.binding) + returning self do |adapter| + instance_eval(&block) + end + end + + def method_missing(method, *args, &block) + @caller.send(method, *args, &block) + end +end
\ No newline at end of file |