Class: SQLStatement::Update

Inherits:

Select

• Object
• Select
• SQLStatement::Update

Defined in:

lib/sql/statement.rb

Overview

Creates a statement of the form

UPDATE tables SET field=value, field2=value2 WHERE ...

This descends from SelectStatement. Even though the strings are very different, they have lots of other stuff in common.

Instance Attribute Summary

Attributes inherited from Select

#distinct, #straight_join

Instance Method Summary

• #field(expression, targetfield) ⇒ Object

  Set a field to contain a value.

• #placeheld ⇒ Object
• #to_s ⇒ Object

Methods inherited from Select

#+, #<<, #allfields, #condition, #groupby, #initialize, #leftjoin, newlists, #orderby, #table, #to_sqlpart

Constructor Details

This class inherits a constructor from SQLStatement::Select

Instance Method Details

#field(expression, targetfield) ⇒ Object

Set a field to contain a value. Note the order of the parameters matches the order used for the Select statement

# File 'lib/sql/statement.rb', line 450

def field expression, targetfield
  super expression, targetfield
end

#placeheld ⇒ Object

# File 'lib/sql/statement.rb', line 444

def placeheld
   (@table_names+allfields[1]+conditions).collect{|x| x.placeheld}.flatten
end

#to_s ⇒ Object

# File 'lib/sql/statement.rb', line 438

def to_s
   statement="UPDATE #{tables_s} SET #{updatepart_s}"
   v=conditions_s; statement << " WHERE "<< v if v
   statement
end