Class: Amalgalite::Column

Inherits:
Object
  • Object
show all
Defined in:
lib/amalgalite/column.rb

Overview

a class representing the meta information about an SQLite column, this class serves both for general Schema level information, and for result set information from a SELECT query.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(db, table, name, order, as_name = nil) ⇒ Column

Create a column with its name and associated table



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# File 'lib/amalgalite/column.rb', line 57

def initialize( db, table, name, order, as_name = nil)
  @db                 = db
  @table              = table
  @name               = name
  @order              = Float(order).to_i
  @as_name            = as_name || name
  @declared_data_type = nil
  @normalized_declared_data_type = nil
  @default_value      = nil
end

Instance Attribute Details

#as_name ⇒ Object

The column “as” name. This is what its name is in the query, if this is part of the query, then this is the result, otherwise it is the name



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# File 'lib/amalgalite/column.rb', line 32

def as_name
  @as_name
end

#collation_sequence_name ⇒ Object

the collation sequence name of the column



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# File 'lib/amalgalite/column.rb', line 48

def collation_sequence_name
  @collation_sequence_name
end

#db ⇒ Object

the database name this column belongs to. This will be ‘main’ for the main database, ‘temp’ for the temp database and whatever an attached database was attached as.



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# File 'lib/amalgalite/column.rb', line 22

def db
  @db
end

#declared_data_type ⇒ Object

the declared data type of the column in the original sql that created the column



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# File 'lib/amalgalite/column.rb', line 42

def declared_data_type
  @declared_data_type
end

#default_value ⇒ Object

the default value of the column. This may not have a value and that either means that there is no default value, or one could not be determined.



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# File 'lib/amalgalite/column.rb', line 38

def default_value
  @default_value
end

#name ⇒ Object

the column name



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# File 'lib/amalgalite/column.rb', line 28

def name
  @name
end

#normalized_declared_data_type ⇒ Object (readonly)

the declared data type that is tokenized and then downcased



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# File 'lib/amalgalite/column.rb', line 45

def normalized_declared_data_type
  @normalized_declared_data_type
end

#order ⇒ Object

The index (starting with 0) of this column in the table definition or result set



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# File 'lib/amalgalite/column.rb', line 52

def order
  @order
end

#schema ⇒ Object

the schema object this column is associated with



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# File 'lib/amalgalite/column.rb', line 17

def schema
  @schema
end

#table ⇒ Object

the table to which this column belongs



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# File 'lib/amalgalite/column.rb', line 25

def table
  @table
end

Instance Method Details

#auto_increment=(other) ⇒ Object

set whether or not the column is auto increment



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# File 'lib/amalgalite/column.rb', line 108

def auto_increment=( other )
  @auto_increment = Boolean.to_bool( other )
end

#auto_increment? ⇒ Boolean

true if the column is auto increment

Returns:



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# File 'lib/amalgalite/column.rb', line 113

def auto_increment?
  @auto_increment
end

#has_default_value? ⇒ Boolean

true if the column has a default value

Returns:



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# File 'lib/amalgalite/column.rb', line 78

def has_default_value?
  not default_value.nil?
end

#not_null_constraint=(other) ⇒ Object

set whether or not the column has a not null constraint



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# File 'lib/amalgalite/column.rb', line 88

def not_null_constraint=( other )
  @not_null_constraint = Boolean.to_bool( other )
end

#not_null_constraint? ⇒ Boolean

true if the column as a NOT NULL constraint

Returns:



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# File 'lib/amalgalite/column.rb', line 93

def not_null_constraint?
  @not_null_constraint
end

#nullable? ⇒ Boolean

true if the column may have a NULL value

Returns:



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# File 'lib/amalgalite/column.rb', line 83

def nullable?
  @not_null_constraint == false
end

#primary_key=(other) ⇒ Object

set whether or not the column is a primary key column



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# File 'lib/amalgalite/column.rb', line 98

def primary_key=( other )
  @primary_key = Boolean.to_bool( other )
end

#primary_key? ⇒ Boolean

true if the column is a primary key column

Returns:



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# File 'lib/amalgalite/column.rb', line 103

def primary_key?
  @primary_key
end