Class: DBI::DBD::SQLite3::Database

Inherits:
BaseDatabase
  • Object
show all
Defined in:
lib/dbd/sqlite3/database.rb

Overview

See DBI::BaseDatabase.

Instance Method Summary collapse

Constructor Details

#initialize(dbname, attr) ⇒ Database

Constructor. Valid attributes:

  • AutoCommit: Commit after every statement execution.

The following attributes go directly to the low-level SQLite3 driver. Please consult it’s documentation for more information.

  • auto_vacuum

  • cache_size

  • default_cache_size

  • default_synchronous

  • default_temp_store

  • full_column_names

  • synchronous

  • temp_store

  • type_translation



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# File 'lib/dbd/sqlite3/database.rb', line 23

def initialize(dbname, attr)
    @db = ::SQLite3::Database.new(dbname)

    @db.type_translation = false

    @attr = {'AutoCommit' => true}
    if attr then
        attr.each_pair do |key, value|
            begin
                self[key] = value
            rescue DBI::NotSupportedError
            end
        end
    end
    __generate_attr__
end

Instance Method Details

#[]=(attr, value) ⇒ Object

See #new for valid attributes.

If Autocommit is set to true, commit happens immediately if a transaction is open.



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# File 'lib/dbd/sqlite3/database.rb', line 171

def []=(attr, value)
    case attr
    when 'AutoCommit'
        if value
            @db.commit if @db.transaction_active?
        else
            @db.transaction unless @db.transaction_active?
        end
    @attr[attr] = value
    when 'auto_vacuum', 'cache_size', 'count_changes',
      'default_cache_size', 'encoding', 'full_column_names',
      'page_size', 'short_column_names', 'synchronous',
      'temp_store', 'temp_store_directory'
      @db.__send__((attr+'='), value)
        @attr[attr] = @db.__send__(attr)
    when 'busy_timeout'
        @db.busy_timeout(value)
        @attr[attr] = value
    when 'busy_handler'
        @db.busy_timeout(&value)
        @attr[attr] = value
    when 'type_translation'
        @db.type_translation = value
        @attr[attr] = value
    else
        raise DBI::NotSupportedError
    end

    return value
end

#__generate_attr__ ⇒ Object

This method is used to aid the constructor and probably should not be used independently.



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# File 'lib/dbd/sqlite3/database.rb', line 152

def __generate_attr__()
    tt = @db.type_translation
    @db.type_translation = false
    [ 'auto_vacuum', 'cache_size', 'default_cache_size',
    'default_synchronous', 'default_temp_store', 'full_column_names',
    'synchronous', 'temp_store', 'type_translation' ].each do |key|
        unless @attr.has_key?(key) then
            @attr[key] = @db.__send__(key)
        end
    end
    @db.type_translation = tt
end

#columns(table) ⇒ Object

See DBI::BaseDatabase#columns.

Additional Attributes:

  • sql_type: XOPEN integer SQL Type.

  • nullable: true if NULL is allowed in this column.

  • default: the value that will be used in new rows if this column receives no data.



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# File 'lib/dbd/sqlite3/database.rb', line 115

def columns(table)
    @db.type_translation = false
    ret =
        @db.table_info(table).map do |hash|
            m = DBI::DBD::SQLite3.parse_type(hash['type'])
            h = { 
                'name' => hash['name'],
                'type_name' => m[1],
                'sql_type' => 
                    begin
                        DBI.const_get('SQL_'+hash['type'].upcase)
                    rescue NameError
                        DBI::SQL_OTHER
                    end,
                'nullable' => (hash['notnull'] == '0'),
                'default' => (@attr['type_translation'] && (not hash['dflt_value'])) ? 
                                @db.translator.translate(hash['type'], hash['dflt_value']) :
                                hash['dflt_value'] 
            }

            h['precision'] = m[3].to_i if m[3]
            h['scale']     = m[5].to_i if m[5]

            h
        end
    @db.type_translation = @attr['type_translation']
    ret
end

#commit ⇒ Object 



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# File 'lib/dbd/sqlite3/database.rb', line 62

def commit()
    if @db.transaction_active?
        @db.commit
        @db.transaction
    else
        raise DBI::ProgrammingError.new("No active transaction.")
    end
end

#database_name ⇒ Object 



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# File 'lib/dbd/sqlite3/database.rb', line 49

def database_name
    st = DBI::DBD::SQLite3::Statement.new('PRAGMA database_list', @db)
    st.execute
    row = st.fetch
    st.finish

    return row[2]
end

#disconnect ⇒ Object 



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# File 'lib/dbd/sqlite3/database.rb', line 40

def disconnect()
    @db.rollback if @db.transaction_active?
    @db.close
end

#ping ⇒ Object 



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# File 'lib/dbd/sqlite3/database.rb', line 58

def ping()
    not @db.closed?
end

#prepare(statement) ⇒ Object 



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# File 'lib/dbd/sqlite3/database.rb', line 45

def prepare(statement)
    DBI::DBD::SQLite3::Statement.new(statement, @db)
end

#quote(value) ⇒ Object 



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# File 'lib/dbd/sqlite3/database.rb', line 144

def quote(value)
    ::SQLite3::Database.quote(value.to_s)
end

#rollback ⇒ Object

See DBI::BaseDatabase#rollback.

If all statements were not closed before the rollback occurs, a DBI::Warning may be raised if the database encounters an error because of it.

This method will also raise DBI::ProgrammingError if not in a transaction.



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# File 'lib/dbd/sqlite3/database.rb', line 81

def rollback()
    if @db.transaction_active?
        begin 
            @db.rollback 
            @db.transaction
        rescue Exception => e
            raise DBI::Warning, "Statements were not closed prior to rollback"
        end
    else
        raise DBI::ProgrammingError.new("No active transaction.")
    end
end

#tables ⇒ Object 



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# File 'lib/dbd/sqlite3/database.rb', line 94

def tables()
    ret = []
    result = @db.execute(%q(
        SELECT name FROM sqlite_master WHERE type IN ('table', 'view') 
        UNION ALL 
        SELECT name FROM sqlite_temp_master WHERE type in ('table', 'view') ORDER BY 1
    ))
    result.each{|row| ret.push(row[0])}
    ret
end