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/CakePHP 3.8

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

Cake\Database\Expression\Comparison implements Cake\Database\ExpressionInterface, Cake\Database\Expression\FieldInterface uses Cake\Database\Type\ExpressionTypeCasterTrait , Cake\Database\Expression\FieldTrait

Direct Subclasses

Properties summary

  • $_isMultiple protected
    boolean
    Whether or not the value in this expression is a traversable
  • $_operator protected
    string
    The operator used for comparing field and value
  • $_type protected
    string|array
    The type to be used for casting the value to a database representation
  • $_value protected
    mixed
    The value to be used in the right hand side of the operation
  • $_valueExpressions protected

    A cached list of ExpressionInterface objects that were found in the value for this expression.

Inherited Properties

Method Summary

  • __clone() public
    Create a deep clone.
  • __construct() public
    Constructor
  • _bindValue() protected
    Registers a value in the placeholder generator and returns the generated placeholder
  • Returns an array with the original $values in the first position and all ExpressionInterface objects that could be found in the second position.

  • _flattenValue() protected

    Converts a traversable value into a set of placeholders generated by $generator and separated by ,

  • Returns a template and a placeholder for the value after registering it with the placeholder $generator

  • getOperator() public
    Returns the operator used for comparison
  • getValue() public
    Returns the value used for comparison
  • setOperator() public
    Sets the operator to use for the comparison
  • setValue() public
    Sets the value
  • sql() public
    Convert the expression into a SQL fragment.
  • 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()source public

__clone( )

Create a deep clone.

Clones the field and value if they are expression objects.

__construct()source public

__construct( string|Cake\Database\ExpressionInterface $field , mixed $value , string $type , string $operator )

Constructor

Parameters

string|Cake\Database\ExpressionInterface $field
the field name to compare to a value
mixed $value
The value to be used in comparison
string $type
the type name used to cast the value
string $operator
the operator used for comparing field and value

_bindValue()source protected

_bindValue( mixed $value , Cake\Database\ValueBinder $generator , string $type )

Registers a value in the placeholder generator and returns the generated placeholder

Parameters

mixed $value
The value to bind
Cake\Database\ValueBinder $generator
The value binder to use
string $type
The type of $value

Returns

string
generated placeholder

_collectExpressions()source protected

_collectExpressions( array|Traversable $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

array|Traversable $values
The rows to insert

Returns

array

_flattenValue()source protected

_flattenValue( array|Traversable $value , Cake\Database\ValueBinder $generator , string|array|null $type = 'string' )

Converts a traversable value into a set of placeholders generated by $generator and separated by ,

Parameters

array|Traversable $value
the value to flatten
Cake\Database\ValueBinder $generator
The value binder to use
string|array|null $type optional 'string'
the type to cast values to

Returns

string

_stringExpression()source protected

_stringExpression( Cake\Database\ValueBinder $generator )

Returns a template and a placeholder for the value after registering it with the placeholder $generator

Parameters

Cake\Database\ValueBinder $generator
The value binder to use.

Returns

array
First position containing the template and the second a placeholder

getOperator()source public

getOperator( )

Returns the operator used for comparison

Returns

string

getValue()source public

getValue( )

Returns the value used for comparison

Returns

mixed

setOperator()source public

setOperator( string $operator )

Sets the operator to use for the comparison

Parameters

string $operator
The operator to be used for the comparison.

setValue()source public

setValue( mixed $value )

Sets the value

Parameters

mixed $value
The value to compare

sql()source public

sql( Cake\Database\ValueBinder $generator )

Convert the expression into a SQL fragment.

Parameters

Cake\Database\ValueBinder $generator
Placeholder generator object

Returns

string

Implementation of

Cake\Database\ExpressionInterface::sql()

traverse()source public

traverse( callable $callable )

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

callable $callable
$visitor The callable to apply to all nodes.

Implementation of

Cake\Database\ExpressionInterface::traverse()

Methods used from Cake\Database\Type\ExpressionTypeCasterTrait

_castToExpression()source 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

mixed $value
The value to converto to ExpressionInterface
string $type
The type name

Returns

mixed

_requiresToExpressionCasting()source 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

array $types
List of type names

Returns

array

Methods used from Cake\Database\Expression\FieldTrait

getField()source public

getField( )

Returns the field name

Returns

string|Cake\Database\ExpressionInterface

setField()source public

setField( string|Cake\Database\ExpressionInterface $field )

Sets the field name

Parameters

string|Cake\Database\ExpressionInterface $field
The field to compare with.

Properties detail

$_isMultiplesource

protected boolean

Whether or not the value in this expression is a traversable

false

$_operatorsource

protected string

The operator used for comparing field and value

$_typesource

protected string|array

The type to be used for casting the value to a database representation

$_valuesource

protected mixed

The value to be used in the right hand side of the operation

$_valueExpressionssource

protected Cake\Database\ExpressionInterface[]

A cached list of ExpressionInterface objects that were found in the value for this expression.

[]

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https://api.cakephp.org/3.8/class-Cake.Database.Expression.Comparison.html