module Sequel::MySQL::DatabaseMethods

Methods shared by Database instances that connect to MySQL, currently supported by the native and JDBC adapters.

Constants

AUTO_INCREMENT
CAST_TYPES
COLUMN_DEFINITION_ORDER
DATABASE_ERROR_REGEXPS
MYSQL_TIMESTAMP_RE
PRIMARY

Public Instance Methods

cast_type_literal(type) click to toggle source

MySQL’s cast rules are restrictive in that you can’t just cast to any possible database type.

# File lib/sequel/adapters/shared/mysql.rb, line 56
def cast_type_literal(type)
  CAST_TYPES[type] || super
end
commit_prepared_transaction(transaction_id, opts=OPTS) click to toggle source

Commit an existing prepared transaction with the given transaction identifier string.

# File lib/sequel/adapters/shared/mysql.rb, line 62
def commit_prepared_transaction(transaction_id, opts=OPTS)
  run("XA COMMIT #{literal(transaction_id)}", opts)
end
database_type() click to toggle source

MySQL uses the :mysql database type

# File lib/sequel/adapters/shared/mysql.rb, line 67
def database_type
  :mysql
end
foreign_key_list(table, opts=OPTS) click to toggle source

Use the Information Schema’s KEY_COLUMN_USAGE table to get basic information on foreign key columns, but include the constraint name.

# File lib/sequel/adapters/shared/mysql.rb, line 74
def foreign_key_list(table, opts=OPTS)
  m = output_identifier_meth
  im = input_identifier_meth
  ds = metadata_dataset.
    from(Sequel[:INFORMATION_SCHEMA][:KEY_COLUMN_USAGE]).
    where(:TABLE_NAME=>im.call(table), :TABLE_SCHEMA=>Sequel.function(:DATABASE)).
    exclude(:CONSTRAINT_NAME=>'PRIMARY').
    exclude(:REFERENCED_TABLE_NAME=>nil).
    select(Sequel[:CONSTRAINT_NAME].as(:name), Sequel[:COLUMN_NAME].as(:column), Sequel[:REFERENCED_TABLE_NAME].as(:table), Sequel[:REFERENCED_COLUMN_NAME].as(:key))
  
  h = {}
  ds.each do |row|
    if r = h[row[:name]]
      r[:columns] << m.call(row[:column])
      r[:key] << m.call(row[:key])
    else
      h[row[:name]] = {:name=>m.call(row[:name]), :columns=>[m.call(row[:column])], :table=>m.call(row[:table]), :key=>[m.call(row[:key])]}
    end
  end
  h.values
end
freeze() click to toggle source
# File lib/sequel/adapters/shared/mysql.rb, line 96
def freeze
  server_version
  supports_timestamp_usecs?
  super
end
global_index_namespace?() click to toggle source

MySQL namespaces indexes per table.

# File lib/sequel/adapters/shared/mysql.rb, line 103
def global_index_namespace?
  false
end
indexes(table, opts=OPTS) click to toggle source

Use SHOW INDEX FROM to get the index information for the table.

By default partial indexes are not included, you can use the option :partial to override this.

# File lib/sequel/adapters/shared/mysql.rb, line 112
def indexes(table, opts=OPTS)
  indexes = {}
  remove_indexes = []
  m = output_identifier_meth
  im = input_identifier_meth
  schema, table = schema_and_table(table)

  table = Sequel::SQL::Identifier.new(table)
  sql = "SHOW INDEX FROM #{literal(table)}"
  if schema
    schema = Sequel::SQL::Identifier.new(schema)
    sql += " FROM #{literal(schema)}"
  end

  metadata_dataset.with_sql(sql).each do |r|
    name = r[:Key_name]
    next if name == 'PRIMARY'
    name = m.call(name)
    remove_indexes << name if r[:Sub_part] && ! opts[:partial]
    i = indexes[name] ||= {:columns=>[], :unique=>r[:Non_unique] != 1}
    i[:columns] << m.call(r[:Column_name])
  end
  indexes.reject{|k,v| remove_indexes.include?(k)}
end
rollback_prepared_transaction(transaction_id, opts=OPTS) click to toggle source

Rollback an existing prepared transaction with the given transaction identifier string.

# File lib/sequel/adapters/shared/mysql.rb, line 139
def rollback_prepared_transaction(transaction_id, opts=OPTS)
  run("XA ROLLBACK #{literal(transaction_id)}", opts)
end
server_version() click to toggle source

Get version of MySQL server, used for determined capabilities.

# File lib/sequel/adapters/shared/mysql.rb, line 144
def server_version
  @server_version ||= begin
    m = /(\d+)\.(\d+)\.(\d+)/.match(get(SQL::Function.new(:version)))
    (m[1].to_i * 10000) + (m[2].to_i * 100) + m[3].to_i
  end
end
supports_create_table_if_not_exists?() click to toggle source

MySQL supports CREATE TABLE IF NOT EXISTS syntax.

# File lib/sequel/adapters/shared/mysql.rb, line 152
def supports_create_table_if_not_exists?
  true
end
supports_prepared_transactions?() click to toggle source

MySQL 5+ supports prepared transactions (two-phase commit) using XA

# File lib/sequel/adapters/shared/mysql.rb, line 157
def supports_prepared_transactions?
  server_version >= 50000
end
supports_savepoints?() click to toggle source

MySQL 5+ supports savepoints

# File lib/sequel/adapters/shared/mysql.rb, line 162
def supports_savepoints?
  server_version >= 50000
end
supports_savepoints_in_prepared_transactions?() click to toggle source

MySQL doesn’t support savepoints inside prepared transactions in from 5.5.12 to 5.5.23, see bugs.mysql.com/bug.php?id=64374

# File lib/sequel/adapters/shared/mysql.rb, line 168
def supports_savepoints_in_prepared_transactions?
  super && (server_version <= 50512 || server_version >= 50523)
end
supports_timestamp_usecs?() click to toggle source

Support fractional timestamps on MySQL 5.6.5+ if the :fractional_seconds Database option is used. Technically, MySQL 5.6.4+ supports them, but automatic initialization of datetime values wasn’t supported to 5.6.5+, and this is related to that.

# File lib/sequel/adapters/shared/mysql.rb, line 176
def supports_timestamp_usecs?
  return @supports_timestamp_usecs if defined?(@supports_timestamp_usecs)
  @supports_timestamp_usecs = server_version >= 50605 && typecast_value_boolean(opts[:fractional_seconds])
end
supports_transaction_isolation_levels?() click to toggle source

MySQL supports transaction isolation levels

# File lib/sequel/adapters/shared/mysql.rb, line 182
def supports_transaction_isolation_levels?
  true
end
tables(opts=OPTS) click to toggle source

Return an array of symbols specifying table names in the current database.

Options:

:server

Set the server to use

# File lib/sequel/adapters/shared/mysql.rb, line 190
def tables(opts=OPTS)
  full_tables('BASE TABLE', opts)
end
use(db_name) click to toggle source

Changes the database in use by issuing a USE statement. I would be very careful if I used this.

# File lib/sequel/adapters/shared/mysql.rb, line 196
def use(db_name)
  Sequel::Deprecation.deprecate("Database#use", "Create a new Sequel::Database instance instead of using Database#use")
  disconnect
  @opts[:database] = db_name if self << "USE #{db_name}"
  @schemas = {}
  self
end
views(opts=OPTS) click to toggle source

Return an array of symbols specifying view names in the current database.

Options:

:server

Set the server to use

# File lib/sequel/adapters/shared/mysql.rb, line 208
def views(opts=OPTS)
  full_tables('VIEW', opts)
end