Current File : /home/rs/ruby/1.8/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb
module DBI::DBD::Mysql
#
# Models the DBI::BaseStatement API to create DBI::StatementHandle objects.
#
class Statement < DBI::BaseStatement
include Util
def initialize(parent, handle, statement, mutex)
super(nil)
@parent, @handle, @mutex = parent, handle, mutex
@params = []
@prep_stmt = DBI::SQL::PreparedStatement.new(@parent, statement)
end
#
# See DBI::BaseStatement#bind_param. This method will also raise
# DBI::InterfaceError if +param+ is not a Fixnum, to prevent incorrect
# binding.
#
def bind_param(param, value, attribs)
raise InterfaceError, "only ? parameters supported" unless param.is_a? Fixnum
@params[param-1] = value
end
#
# See DBI::BaseStatement#execute. If DBI thinks this is a query via DBI::SQL.query?(),
# it will force the row processed count to 0. Otherwise, it will return
# what MySQL thinks is the row processed count.
#
def execute
sql = @prep_stmt.bind(@params)
@mutex.synchronize {
@handle.query_with_result = true
@res_handle = @handle.query(sql)
@column_info = self.column_info
@current_row = 0
@rows = DBI::SQL.query?(sql) ? 0 : @handle.affected_rows
}
rescue MyError => err
error(err)
end
def finish
@res_handle.free if @res_handle
rescue MyError => err
error(err)
end
#
# Helper method to aid #fetch. Do not call directly.
#
def fill_array(rowdata)
return nil if rowdata.nil?
return rowdata.dup
end
def fetch
@current_row += 1
fill_array(@res_handle.fetch_row)
rescue MyError => err
error(err)
end
#
# See DBI::BaseStatement#fetch_scroll. These additional constants are also supported:
#
# * DBI::SQL_FETCH_PRIOR: Fetch the row previous to the current one.
# * DBI::SQL_FETCH_FIRST: Fetch the first row.
# * DBI::SQL_FETCH_ABSOLUTE: Fetch the row at the offset provided.
# * DBI::SQL_FETCH_RELATIVE: Fetch the row at the current point + offset.
#
def fetch_scroll(direction, offset)
case direction
when DBI::SQL_FETCH_NEXT
@current_row += 1
fill_array(@res_handle.fetch_row)
when DBI::SQL_FETCH_PRIOR
@res_handle.data_seek(@current_row - 1)
fill_array(@res_handle.fetch_row)
when DBI::SQL_FETCH_FIRST
@current_row = 1
@res_handle.data_seek(@current_row - 1)
fill_array(@res_handle.fetch_row)
when DBI::SQL_FETCH_LAST
@current_row = @res_handle.num_rows
@res_handle.data_seek(@current_row - 1)
fill_array(@res_handle.fetch_row)
when DBI::SQL_FETCH_ABSOLUTE
@current_row = offset + 1
@res_handle.data_seek(@current_row - 1)
fill_array(@res_handle.fetch_row)
when DBI::SQL_FETCH_RELATIVE
@current_row += offset + 1
@res_handle.data_seek(@current_row - 1)
fill_array(@res_handle.fetch_row)
else
raise NotSupportedError
end
#end
end
#
# See DBI::BaseStatement#column_info, and DBI::DBD::Mysql::Database#columns.
#
# This method provides all the attributes the +columns+ method
# provides, and a few others:
#
# * mysql_type: These correspond to constants in the Mysql::Types
# package, in the lower-level 'mysql' package.
# * mysql_type_name: A text representation of +mysql_type+.
# * mysql_length: The length of the column.
# * mysql_max_length: The max length of the column. FIXME DESCRIBE
# DIFFERENCE
# * mysql_flags: Internal MySQL flags on this column.
#
def column_info
retval = []
return [] if @res_handle.nil?
unique_key_flag = MysqlField.const_get(:UNIQUE_KEY_FLAG)
multiple_key_flag = MysqlField.const_get(:MULTIPLE_KEY_FLAG)
indexed = (unique_key_flag | multiple_key_flag)
# Note: Cannot get 'default' column attribute because MysqlField.def
# is set only by mysql_list_fields()
@res_handle.fetch_fields.each {|col|
mysql_type_name, dbi_type = Database::TYPE_MAP[col.type] rescue [nil, nil]
xopen_info = Database::MYSQL_to_XOPEN[mysql_type_name] ||
Database::MYSQL_to_XOPEN[nil]
sql_type = xopen_info[0]
type_name = DBI::SQL_TYPE_NAMES[sql_type]
retval << {
# Standard Ruby DBI column attributes
'name' => col.name,
'sql_type' => sql_type,
'type_name' => type_name,
# XXX it seems mysql counts the literal decimal point when weighing in the "length".
'precision' => type_name == "NUMERIC" ? col.length - 2 : col.length,
'scale' => col.decimals,
'nullable' => !col.is_not_null?,
'indexed' => ((col.flags & indexed) != 0) ||
col.is_pri_key?,
'primary' => col.is_pri_key?,
'unique' => ((col.flags & unique_key_flag) != 0) ||
col.is_pri_key?,
# MySQL-specific attributes (signified by leading "mysql_")
'mysql_type' => col.type,
'mysql_type_name' => mysql_type_name,
'mysql_length' => col.length,
'mysql_max_length' => col.max_length,
'mysql_flags' => col.flags
}
if retval[-1]['sql_type'] == DBI::SQL_TINYINT and retval[-1]['precision'] == 1
retval[-1]['dbi_type'] = DBI::Type::Boolean
elsif dbi_type
retval[-1]['dbi_type'] = dbi_type
end
}
retval
rescue MyError => err
error(err)
end
def rows
@rows
end
# def []=(attr, value)
# case attr
# when 'mysql_use_result'
# @attr['mysql_store_result'] = ! value
# @attr['mysql_use_result'] = value
# when 'mysql_store_result'
# @attr['mysql_use_result'] = ! value
# @attr['mysql_store_result'] = value
# else
# raise NotSupportedError
# end
# end
end # class Statement
end
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