Class Comparison
A Comparison is a type of query expression that represents an operation
involving a field an operator and a value. In its most common form the
string representation of a comparison is field = value
Properties summary
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$_field protected
string|array|\Cake\Database\ExpressionInterfaceThe field name or expression to be used in the left hand side of the operator
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$_isMultiple protected
boolWhether or not the value in this expression is a traversable
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$_operator protected
stringThe operator used for comparing field and value
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$_type protected
string|nullThe type to be used for casting the value to a database representation
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$_value protected
mixedThe value to be used in the right hand side of the operation
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$_valueExpressions protected
\Cake\Database\ExpressionInterface[]A cached list of ExpressionInterface objects that were found in the value for this expression.
Method Summary
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__clone() public
Create a deep clone.
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__construct() public
Constructor
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_bindValue() protected
Registers a value in the placeholder generator and returns the generated placeholder
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_castToExpression() protected
Conditionally converts the passed value to an ExpressionInterface object if the type class implements the ExpressionTypeInterface. Otherwise, returns the value unmodified.
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_collectExpressions() protected
Returns an array with the original $values in the first position and all ExpressionInterface objects that could be found in the second position.
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_flattenValue() protected
Converts a traversable value into a set of placeholders generated by $generator and separated by
, -
_requiresToExpressionCasting() protected
Returns an array with the types that require values to be casted to expressions, out of the list of type names passed as parameter.
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_stringExpression() protected
Returns a template and a placeholder for the value after registering it with the placeholder $generator
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getField() public
Returns the field name
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getOperator() public
Returns the operator used for comparison
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getValue() public
Returns the value used for comparison
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setField() public
Sets the field name
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setOperator() public
Sets the operator to use for the comparison
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setValue() public
Sets the value
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sql() public
Convert the expression into a SQL fragment.
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traverse() public
Iterates over each part of the expression recursively for every level of the expressions tree and executes the $visitor callable passing as first parameter the instance of the expression currently being iterated.
Method Detail
__clone() public ¶
__clone()
Create a deep clone.
Clones the field and value if they are expression objects.
__construct() public ¶
__construct(mixed $field, mixed $value, ?string $type, string $operator)
Constructor
Parameters
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string|\Cake\Database\ExpressionInterface$field the field name to compare to a value
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mixed$value The value to be used in comparison
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string|null$type optional the type name used to cast the value
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string$operator optional the operator used for comparing field and value
_bindValue() protected ¶
_bindValue(mixed $value, \Cake\Database\ValueBinder $generator, ?string $type)
Registers a value in the placeholder generator and returns the generated placeholder
Parameters
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mixed$value The value to bind
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\Cake\Database\ValueBinder$generator The value binder to use
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string|null$type optional The type of $value
Returns
stringgenerated placeholder
_castToExpression() protected ¶
_castToExpression(mixed $value, ?string $type)
Conditionally converts the passed value to an ExpressionInterface object if the type class implements the ExpressionTypeInterface. Otherwise, returns the value unmodified.
Parameters
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mixed$value The value to converto to ExpressionInterface
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string|null$type optional The type name
Returns
mixed_collectExpressions() protected ¶
_collectExpressions(mixed $values)
Returns an array with the original $values in the first position and all ExpressionInterface objects that could be found in the second position.
Parameters
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iterable|\Cake\Database\ExpressionInterface$values The rows to insert
Returns
array_flattenValue() protected ¶
_flattenValue(iterable $value, \Cake\Database\ValueBinder $generator, ?string $type)
Converts a traversable value into a set of placeholders generated by
$generator and separated by ,
Parameters
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iterable$value the value to flatten
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\Cake\Database\ValueBinder$generator The value binder to use
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string|null$type optional the type to cast values to
Returns
string_requiresToExpressionCasting() protected ¶
_requiresToExpressionCasting(array $types)
Returns an array with the types that require values to be casted to expressions, out of the list of type names passed as parameter.
Parameters
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array$types List of type names
Returns
array_stringExpression() protected ¶
_stringExpression(\Cake\Database\ValueBinder $generator)
Returns a template and a placeholder for the value after registering it with the placeholder $generator
Parameters
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\Cake\Database\ValueBinder$generator The value binder to use.
Returns
arrayFirst position containing the template and the second a placeholder
getField() public ¶
getField()
Returns the field name
Returns
string|array|\Cake\Database\ExpressionInterfacesetField() public ¶
setField(mixed $field)
Sets the field name
Parameters
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string|array|\Cake\Database\ExpressionInterface$field The field to compare with.
setOperator() public ¶
setOperator(string $operator)
Sets the operator to use for the comparison
Parameters
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string$operator The operator to be used for the comparison.
setValue() public ¶
setValue(mixed $value)
Sets the value
Parameters
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mixed$value The value to compare
sql() public ¶
sql(\Cake\Database\ValueBinder $generator)
Convert the expression into a SQL fragment.
Parameters
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\Cake\Database\ValueBinder$generator Placeholder generator object
Returns
stringtraverse() public ¶
traverse(\Closure $visitor)
Iterates over each part of the expression recursively for every level of the expressions tree and executes the $visitor callable passing as first parameter the instance of the expression currently being iterated.
Parameters
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\Closure$visitor The callable to apply to all nodes.
Returns
$thisProperty Detail
$_field ¶ protected
The field name or expression to be used in the left hand side of the operator
Type
string|array|\Cake\Database\ExpressionInterface$_type ¶ protected
The type to be used for casting the value to a database representation
Type
string|null$_valueExpressions ¶ protected
A cached list of ExpressionInterface objects that were found in the value for this expression.
Type
\Cake\Database\ExpressionInterface[]