Class: Sequel::Schema::DbSchemaParser

Inherits:
Object
  • Object
show all
Defined in:
lib/sequel/schema/db_schema_parser.rb

Overview

Builds an abstract representation of a database schema.

Sample usage:

parser = DbSchemaParser.for_db( sequel_db_connection )
parser.parse_db_schema 
# => Returns an array of table definitions

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.for_db(db) ⇒ Object

Returns an appropriate schema parser for the database connection.



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# File 'lib/sequel/schema/db_schema_parser.rb', line 15

def self.for_db(db)
  self.new(db)
end

Instance Method Details

#parse_db_schema ⇒ Object

Parses the schema from a Sequel Database connection.

Returns a hash of table representations.

Example:

builder.parse_db_schema(db)
# => {:table1 => { :columns => [ DbColumns ... ] }
      :table2 => { ... } }



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# File 'lib/sequel/schema/db_schema_parser.rb', line 29

def parse_db_schema
  @db.tables.inject({}) do |result, table_name|
    result[table_name] = {
      :indexes => @db.indexes(table_name, :partial => true),
      :columns => parse_table_schema(@db.schema(table_name))
    }
    result
  end
end

#parse_table_schema(db_schema) ⇒ Object

Extracts an array of hashes representing the columns in the table, given an Array of Arrays returned by DB.schema(:table).



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# File 'lib/sequel/schema/db_schema_parser.rb', line 42

def parse_table_schema(db_schema)
  db_schema.map do |column|
    type = parse_type(column.last[:db_type])
    DbColumn.build_from_hash(:name        => column.first,
                             :default     => extract_default(column),
                             :null        => column.last[:allow_null],
                             :column_type => type,
                             :unsigned    => extract_unsigned(column.last[:db_type], type),
                             :size        => extract_size(column.last[:db_type], type),
                             :elements    => extract_enum_elements(column.last[:db_type], type))
  end
end