Class: SqlPostgres::Delete

Inherits:
Object
  • Object
show all
Defined in:
lib/sqlpostgres/Delete.rb

Overview

This class creates and executes an SQL delete statement.

Instance Method Summary collapse

Constructor Details

#initialize(table, connection = Connection.default) ⇒ Delete

Create a delete statement

table

The table name

connection

If supplied, the connection to use. If not supplied, use the default.



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# File 'lib/sqlpostgres/Delete.rb', line 15

def initialize(table, connection = Connection.default)
  @table = table
  @connection = connection
  @where = []
end

Instance Method Details

#exec(connection = @connection) ⇒ Object

Execute the delete statement

connection

If present, the connection to use. If nil, uses the connection passed to new, or if no connection was passed to new, uses the default connection.



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# File 'lib/sqlpostgres/Delete.rb', line 45

def exec(connection = @connection)
  connection.exec(statement)
end

#statement ⇒ Object

Return the SQL statement



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# File 'lib/sqlpostgres/Delete.rb', line 34

def statement
  "delete from #{@table}#{where_clause}"
end

#where(expression) ⇒ Object

Add a “where” condition to this statement.

expression

The condition. Should be one of:

A string

The expression

An array

An expression converted using #substitute_values



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# File 'lib/sqlpostgres/Delete.rb', line 28

def where(expression)
  @where << Translate.substitute_values(expression)
end