Class | Sequel::SQL::ComplexExpression |
In: |
lib/sequel/sql.rb
|
Parent: | Expression |
Represents a complex SQL expression, with a given operator and one or more attributes (which may also be ComplexExpressions, forming a tree). This class is the backbone of Sequel‘s ruby expression DSL.
This is an abstract class that is not that useful by itself. The subclasses BooleanExpression, NumericExpression, and StringExpression define the behavior of the DSL via operators.
OPERTATOR_INVERSIONS | = | {:AND => :OR, :OR => :AND, :< => :>=, :> => :<=, :<= => :>, :>= => :<, :'=' => :'!=' , :'!=' => :'=', :LIKE => :'NOT LIKE', :'NOT LIKE' => :LIKE, :~ => :'!~', :'!~' => :~, :IN => :'NOT IN', :'NOT IN' => :IN, :IS => :'IS NOT', :'IS NOT' => :IS, :'~*' => :'!~*', :'!~*' => :'~*', :NOT => :NOOP, :NOOP => :NOT, :ILIKE => :'NOT ILIKE', :'NOT ILIKE'=>:ILIKE} | A hash of the opposite for each operator symbol, used for inverting objects. | |
MATHEMATICAL_OPERATORS | = | [:+, :-, :/, :*] | Standard mathematical operators used in NumericMethods | |
BITWISE_OPERATORS | = | [:&, :|, :^, :<<, :>>] | Bitwise mathematical operators used in NumericMethods | |
INEQUALITY_OPERATORS | = | [:<, :>, :<=, :>=] | Inequality operators used in InequalityMethods | |
BOOLEAN_OPERATOR_METHODS | = | {:& => :AND, :| =>:OR} | Hash of ruby operator symbols to SQL operators, used in BooleanMethods | |
IN_OPERATORS | = | [:IN, :'NOT IN'] | Operators that use IN/NOT IN for inclusion/exclusion | |
IS_OPERATORS | = | [:IS, :'IS NOT'] | Operators that use IS, used for special casing to override literal true/false values | |
TWO_ARITY_OPERATORS | = | [:'=', :'!=', :LIKE, :'NOT LIKE', \ :~, :'!~', :'~*', :'!~*', :ILIKE, :'NOT ILIKE'] + \ INEQUALITY_OPERATORS + BITWISE_OPERATORS + IS_OPERATORS + IN_OPERATORS | Operator symbols that take exactly two arguments | |
N_ARITY_OPERATORS | = | [:AND, :OR, :'||'] + MATHEMATICAL_OPERATORS | Operator symbols that take one or more arguments | |
ONE_ARITY_OPERATORS | = | [:NOT, :NOOP, :'B~'] | Operator symbols that take only a single argument | |
CONSTANT_INVERSIONS | = | {Constants::TRUE=>Constants::FALSE, Constants::FALSE=>Constants::TRUE, Constants::NULL=>Constants::NOTNULL, Constants::NOTNULL=>Constants::NULL} | A hash of the opposite for each constant, used for inverting constants. |
args | [R] | An array of args for this object |
op | [R] | The operator symbol for this object |
Set the operator symbol and arguments for this object to the ones given. Convert all args that are hashes or arrays of two element arrays to BooleanExpressions, other than the second arg for an IN/NOT IN operator. Raise an Error if the operator doesn‘t allow boolean input and a boolean argument is given. Raise an Error if the wrong number of arguments for a given operator is used.
# File lib/sequel/sql.rb, line 166 166: def initialize(op, *args) 167: orig_args = args 168: args = args.map{|a| Sequel.condition_specifier?(a) ? SQL::BooleanExpression.from_value_pairs(a) : a} 169: case op 170: when *N_ARITY_OPERATORS 171: raise(Error, "The #{op} operator requires at least 1 argument") unless args.length >= 1 172: old_args = args 173: args = [] 174: old_args.each{|a| a.is_a?(self.class) && a.op == op ? args.concat(a.args) : args.push(a)} 175: when *TWO_ARITY_OPERATORS 176: raise(Error, "The #{op} operator requires precisely 2 arguments") unless args.length == 2 177: # With IN/NOT IN, even if the second argument is an array of two element arrays, 178: # don't convert it into a boolean expression, since it's definitely being used 179: # as a value list. 180: args[1] = orig_args[1] if IN_OPERATORS.include?(op) 181: when *ONE_ARITY_OPERATORS 182: raise(Error, "The #{op} operator requires a single argument") unless args.length == 1 183: else 184: raise(Error, "Invalid operator #{op}") 185: end 186: @op = op 187: @args = args 188: end