Class: Migration::ColumnDropper

Inherits:
Object
  • Object
show all
Defined in:
lib/migration/column_dropper.rb

Class Method Summary collapse

Class Method Details

.drop_readonly(table_name, column_name) ⇒ Object 



31
32
33
34
35
36
37
38
 
# File 'lib/migration/column_dropper.rb', line 31

def self.drop_readonly(table_name, column_name)
  BaseDropper.drop_readonly_function(table_name, column_name)

  # Backward compatibility for old functions created in the public schema
  DB.exec(
    "DROP FUNCTION IF EXISTS #{BaseDropper.old_readonly_function_name(table_name, column_name)} CASCADE",
  )
end

.execute_drop(table, columns) ⇒ Object 



20
21
22
23
24
25
26
27
28
29
 
# File 'lib/migration/column_dropper.rb', line 20

def self.execute_drop(table, columns)
  table = table.to_s

  columns.each do |column|
    column = column.to_s
    self.drop_readonly(table, column)
    # safe cause it is protected on method entry, can not be passed in params
    DB.exec("ALTER TABLE #{table} DROP COLUMN IF EXISTS #{column}")
  end
end

.mark_readonly(table_name, column_name) ⇒ Object 



7
8
9
10
11
12
13
14
15
16
17
18
 
# File 'lib/migration/column_dropper.rb', line 7

def self.mark_readonly(table_name, column_name)
  BaseDropper.create_readonly_function(table_name, column_name)

  DB.exec <<~SQL
    CREATE TRIGGER #{BaseDropper.readonly_trigger_name(table_name, column_name)}
    BEFORE INSERT OR UPDATE OF #{column_name}
    ON #{table_name}
    FOR EACH ROW
    WHEN (NEW.#{column_name} IS NOT NULL)
    EXECUTE PROCEDURE #{BaseDropper.readonly_function_name(table_name, column_name)};
  SQL
end