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Class: Aws::DynamoDB::Types::Condition
- Inherits:
-
Struct
- Object
- Struct
- Aws::DynamoDB::Types::Condition
- Defined in:
- (unknown)
Overview
When passing Condition as input to an Aws::Client method, you can use a vanilla Hash:
{
attribute_value_list: ["value"], # value <Hash,Array,String,Numeric,Boolean,IO,Set,nil>
comparison_operator: "EQ", # required, accepts EQ, NE, IN, LE, LT, GE, GT, BETWEEN, NOT_NULL, NULL, CONTAINS, NOT_CONTAINS, BEGINS_WITH
}
Represents the selection criteria for a Query
or Scan
operation:
-
For a
Query
operation,Condition
is used for specifying theKeyConditions
to use when querying a table or an index. ForKeyConditions
, only the following comparison operators are supported:EQ | LE | LT | GE | GT | BEGINS_WITH | BETWEEN
Condition
is also used in aQueryFilter
, which evaluates the query results and returns only the desired values. -
For a
Scan
operation,Condition
is used in aScanFilter
, which evaluates the scan results and returns only the desired values.
Instance Attribute Summary collapse
-
#attribute_value_list ⇒ Array<Types::AttributeValue>
One or more values to evaluate against the supplied attribute.
-
#comparison_operator ⇒ String
A comparator for evaluating attributes.
Instance Attribute Details
#attribute_value_list ⇒ Array<Types::AttributeValue>
One or more values to evaluate against the supplied attribute. The
number of values in the list depends on the ComparisonOperator
being
used.
For type Number, value comparisons are numeric.
String value comparisons for greater than, equals, or less than are
based on ASCII character code values. For example, a
is greater than
A
, and a
is greater than B
. For a list of code values, see
http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters.
For Binary, DynamoDB treats each byte of the binary data as unsigned when it compares binary values.
#comparison_operator ⇒ String
A comparator for evaluating attributes. For example, equals, greater than, less than, etc.
The following comparison operators are available:
EQ | NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS
| BEGINS_WITH | IN | BETWEEN
The following are descriptions of each comparison operator.
EQ
: Equal.EQ
is supported for all data types, including lists and maps.AttributeValueList
can contain only oneAttributeValue
element of type String, Number, Binary, String Set, Number Set, or Binary Set. If an item contains anAttributeValue
element of a different type than the one provided in the request, the value does not match. For example,`{"S":"6"}`
does not equal`{"N":"6"}`
. Also,`{"N":"6"}`
does not equal{"NS":["6", "2", "1"]}
.NE
: Not equal.NE
is supported for all data types, including lists and maps.AttributeValueList
can contain only oneAttributeValue
of type String, Number, Binary, String Set, Number Set, or Binary Set. If an item contains anAttributeValue
of a different type than the one provided in the request, the value does not match. For example,`{"S":"6"}`
does not equal`{"N":"6"}`
. Also,`{"N":"6"}`
does not equal{"NS":["6", "2", "1"]}
.LE
: Less than or equal.AttributeValueList
can contain only oneAttributeValue
element of type String, Number, or Binary (not a set type). If an item contains anAttributeValue
element of a different type than the one provided in the request, the value does not match. For example,`{"S":"6"}`
does not equal`{"N":"6"}`
. Also,`{"N":"6"}`
does not compare to{"NS":["6", "2", "1"]}
.LT
: Less than.AttributeValueList
can contain only oneAttributeValue
of type String, Number, or Binary (not a set type). If an item contains anAttributeValue
element of a different type than the one provided in the request, the value does not match. For example,`{"S":"6"}`
does not equal`{"N":"6"}`
. Also,`{"N":"6"}`
does not compare to{"NS":["6", "2", "1"]}
.GE
: Greater than or equal.AttributeValueList
can contain only oneAttributeValue
element of type String, Number, or Binary (not a set type). If an item contains anAttributeValue
element of a different type than the one provided in the request, the value does not match. For example,`{"S":"6"}`
does not equal`{"N":"6"}`
. Also,`{"N":"6"}`
does not compare to{"NS":["6", "2", "1"]}
.GT
: Greater than.AttributeValueList
can contain only oneAttributeValue
element of type String, Number, or Binary (not a set type). If an item contains anAttributeValue
element of a different type than the one provided in the request, the value does not match. For example,`{"S":"6"}`
does not equal`{"N":"6"}`
. Also,`{"N":"6"}`
does not compare to{"NS":["6", "2", "1"]}
.NOT_NULL
: The attribute exists.NOT_NULL
is supported for all data types, including lists and maps.This operator tests for the existence of an attribute, not its data type. If the data type of attribute \" a
\" is null, and you evaluate it usingNOT_NULL
, the result is a Booleantrue
. This result is because the attribute \"a
\" exists; its data type is not relevant to theNOT_NULL
comparison operator.NULL
: The attribute does not exist.NULL
is supported for all data types, including lists and maps.This operator tests for the nonexistence of an attribute, not its data type. If the data type of attribute \" a
\" is null, and you evaluate it usingNULL
, the result is a Booleanfalse
. This is because the attribute \"a
\" exists; its data type is not relevant to theNULL
comparison operator.CONTAINS
: Checks for a subsequence, or value in a set.AttributeValueList
can contain only oneAttributeValue
element of type String, Number, or Binary (not a set type). If the target attribute of the comparison is of type String, then the operator checks for a substring match. If the target attribute of the comparison is of type Binary, then the operator looks for a subsequence of the target that matches the input. If the target attribute of the comparison is a set (\"SS
\", \"NS
\", or \"BS
\"), then the operator evaluates to true if it finds an exact match with any member of the set.CONTAINS is supported for lists: When evaluating \"
a CONTAINS b
\", \"a
\" can be a list; however, \"b
\" cannot be a set, a map, or a list.NOT_CONTAINS
: Checks for absence of a subsequence, or absence of a value in a set.AttributeValueList
can contain only oneAttributeValue
element of type String, Number, or Binary (not a set type). If the target attribute of the comparison is a String, then the operator checks for the absence of a substring match. If the target attribute of the comparison is Binary, then the operator checks for the absence of a subsequence of the target that matches the input. If the target attribute of the comparison is a set (\"SS
\", \"NS
\", or \"BS
\"), then the operator evaluates to true if it does not find an exact match with any member of the set.NOT_CONTAINS is supported for lists: When evaluating \"
a NOT CONTAINS b
\", \"a
\" can be a list; however, \"b
\" cannot be a set, a map, or a list.BEGINS_WITH
: Checks for a prefix.AttributeValueList
can contain only oneAttributeValue
of type String or Binary (not a Number or a set type). The target attribute of the comparison must be of type String or Binary (not a Number or a set type).IN
: Checks for matching elements in a list.AttributeValueList
can contain one or moreAttributeValue
elements of type String, Number, or Binary. These attributes are compared against an existing attribute of an item. If any elements of the input are equal to the item attribute, the expression evaluates to true.BETWEEN
: Greater than or equal to the first value, and less than or equal to the second value.AttributeValueList
must contain twoAttributeValue
elements of the same type, either String, Number, or Binary (not a set type). A target attribute matches if the target value is greater than, or equal to, the first element and less than, or equal to, the second element. If an item contains anAttributeValue
element of a different type than the one provided in the request, the value does not match. For example,`{"S":"6"}`
does not compare to`{"N":"6"}`
. Also,`{"N":"6"}`
does not compare to{"NS":["6", "2", "1"]}
For usage examples of AttributeValueList
and ComparisonOperator
, see
Legacy Conditional Parameters in the Amazon DynamoDB Developer
Guide.