Module: ActiveRecord::UpdateInBulk::AbstractAdapter

Included in:
ConnectionAdapters::AbstractAdapter
Defined in:
lib/activerecord-updateinbulk/adapters/abstract_adapter.rb

Overview

Extension points mixed into ActiveRecord::ConnectionAdapters::AbstractAdapter and consumed by the builder/visitor pipeline.

Concrete adapters may override any of these methods to describe their SQL capabilities and VALUES table semantics.

Instance Method Summary collapse

Instance Method Details

#supports_values_tables? ⇒ Boolean

Whether the database supports the SQL VALUES table constructor. When false, Relation#update_in_bulk raises ArgumentError.

Returns:

  • (Boolean) 


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# File 'lib/activerecord-updateinbulk/adapters/abstract_adapter.rb', line 12

def supports_values_tables?
  true
end

#typecast_values_table(values_table, columns) ⇒ Object

Hook for adapters that add explicit type casts to VALUES table entries so column types are correctly inferred by the database.

Receives the values_table (Arel::Nodes::ValuesTable) and columns (an array of ActiveRecord::ConnectionAdapters::Column).

Returns the typecasted Arel node: a new node or values_table itself, possibly modified in place.

The default implementation does no explicit type casting.



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# File 'lib/activerecord-updateinbulk/adapters/abstract_adapter.rb', line 47

def typecast_values_table(values_table, columns)
  values_table
end

#values_table_default_column_names(width) ⇒ Object

Returns an array of width column names used by the database for a VALUES table constructor of the given width. These are the native names assigned to each column position when values_table_requires_aliasing? is false; otherwise they are alias conventions.



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# File 'lib/activerecord-updateinbulk/adapters/abstract_adapter.rb', line 33

def values_table_default_column_names(width)
  (1..width).map { |i| "column#{i}" }
end

#values_table_requires_aliasing? ⇒ Boolean

Whether VALUES table serialization must always include explicit column aliases because there are no default names. This is a mariadb quirk.

Returns:

  • (Boolean) 


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# File 'lib/activerecord-updateinbulk/adapters/abstract_adapter.rb', line 25

def values_table_requires_aliasing?
  false
end

#values_table_row_prefix ⇒ Object

A string prepended to each row literal in the VALUES table constructor. Empty by default, per the standard. MySQL overrides this to "ROW" to produce VALUES ROW(1, 2), ROW(3, 4).



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# File 'lib/activerecord-updateinbulk/adapters/abstract_adapter.rb', line 19

def values_table_row_prefix
  ""
end