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Diffstat (limited to 'lib/arel/engines/sql/formatters.rb')
-rw-r--r-- | lib/arel/engines/sql/formatters.rb | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/lib/arel/engines/sql/formatters.rb b/lib/arel/engines/sql/formatters.rb new file mode 100644 index 0000000000..f82ddf631f --- /dev/null +++ b/lib/arel/engines/sql/formatters.rb @@ -0,0 +1,121 @@ +module Arel + module Sql + class Formatter + attr_reader :environment + delegate :christener, :engine, :to => :environment + delegate :name_for, :to => :christener + delegate :quote_table_name, :quote_column_name, :quote, :to => :engine + + def initialize(environment) + @environment = environment + end + end + + class SelectClause < Formatter + def attribute(attribute) + # FIXME this should check that the column exists + if attribute.name.to_s =~ /^\w*$/ + "#{quote_table_name(name_for(attribute.original_relation))}.#{quote_column_name(attribute.name)}" + (attribute.alias ? " AS #{quote(attribute.alias.to_s)}" : "") + else + attribute.name.to_s + (attribute.alias ? " AS #{quote(attribute.alias.to_s)}" : "") + end + end + + def expression(expression) + if expression.function_sql == "DISTINCT" + "#{expression.function_sql} #{expression.attribute.to_sql(self)}" + (expression.alias ? " AS #{quote_column_name(expression.alias)}" : '') + else + "#{expression.function_sql}(#{expression.attribute.to_sql(self)})" + (expression.alias ? " AS #{quote_column_name(expression.alias)}" : " AS #{expression.function_sql.to_s.downcase}_id") + end + end + + def select(select_sql, table) + "(#{select_sql}) AS #{quote_table_name(name_for(table))}" + end + + def value(value) + value + end + end + + class PassThrough < Formatter + def value(value) + value + end + end + + class WhereClause < PassThrough + end + + class OrderClause < PassThrough + def attribute(attribute) + "#{quote_table_name(name_for(attribute.original_relation))}.#{quote_column_name(attribute.name)}" + end + end + + class GroupClause < PassThrough + def attribute(attribute) + "#{quote_table_name(name_for(attribute.original_relation))}.#{quote_column_name(attribute.name)}" + end + end + + class WhereCondition < Formatter + def attribute(attribute) + "#{quote_table_name(name_for(attribute.original_relation))}.#{quote_column_name(attribute.name)}" + end + + def expression(expression) + "#{expression.function_sql}(#{expression.attribute.to_sql(self)})" + end + + def value(value) + value.to_sql(self) + end + + def scalar(value, column = nil) + quote(value, column) + end + + def select(select_sql, table) + "(#{select_sql})" + end + end + + class SelectStatement < Formatter + def select(select_sql, table) + select_sql + end + end + + class TableReference < Formatter + def select(select_sql, table) + "(#{select_sql}) AS #{quote_table_name(name_for(table))}" + end + + def table(table) + if table.name =~ /^(\w|-)*$/ + quote_table_name(table.name) + (table.name != name_for(table) ? " AS " + quote_table_name(name_for(table)) : '') + else + table.name + (table.name != name_for(table) ? " AS " + (name_for(table)) : '') + end + end + end + + class Attribute < WhereCondition + def scalar(scalar) + quote(scalar, environment.column) + end + + def array(array) + "(" + array.collect { |e| e.to_sql(self) }.join(', ') + ")" + end + + def range(left, right) + "#{left} AND #{right}" + end + end + + class Value < WhereCondition + end + end +end |