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Paws::DynamoDB::Scan(3User Contributed Perl DocumentatiPaws::DynamoDB::Scan(3)

NAME
       Paws::DynamoDB::Scan - Arguments	for method Scan	on Paws::DynamoDB

DESCRIPTION
       This class represents the parameters used for calling the method	Scan
       on the Amazon DynamoDB service. Use the attributes of this class	as
       arguments to method Scan.

       You shouln't make instances of this class. Each attribute should	be
       used as a named argument	in the call to Scan.

       As an example:

	 $service_obj->Scan(Att1 => $value1, Att2 => $value2, ...);

       Values for attributes that are native types (Int, String, Float,	etc)
       can passed as-is	(scalar	values). Values	for complex Types (objects)
       can be passed as	a HashRef. The keys and	values of the hashref will be
       used to instance	the underlying object.

ATTRIBUTES
   AttributesToGet => ArrayRef[Str]
       This is a legacy	parameter, for backward	compatibility. New
       applications should use ProjectionExpression instead. Do	not combine
       legacy parameters and expression	parameters in a	single API call;
       otherwise, DynamoDB will	return a ValidationException exception.

       This parameter allows you to retrieve attributes	of type	List or	Map;
       however,	it cannot retrieve individual elements within a	List or	a Map.

       The names of one	or more	attributes to retrieve.	If no attribute	names
       are provided, then all attributes will be returned. If any of the
       requested attributes are	not found, they	will not appear	in the result.

       Note that AttributesToGet has no	effect on provisioned throughput
       consumption. DynamoDB determines	capacity units consumed	based on item
       size, not on the	amount of data that is returned	to an application.

   ConditionalOperator => Str
       This is a legacy	parameter, for backward	compatibility. New
       applications should use FilterExpression	instead. Do not	combine	legacy
       parameters and expression parameters in a single	API call; otherwise,
       DynamoDB	will return a ValidationException exception.

       A logical operator to apply to the conditions in	a ScanFilter map:

       o   "AND" - If all of the conditions evaluate to	true, then the entire
	   map evaluates to true.

       o   "OR"	- If at	least one of the conditions evaluate to	true, then the
	   entire map evaluates	to true.

       If you omit ConditionalOperator,	then "AND" is the default.

       The operation will succeed only if the entire map evaluates to true.

       This parameter does not support attributes of type List or Map.

   ConsistentRead => Bool
       A Boolean value that determines the read	consistency model during the
       scan:

       o   If ConsistentRead is	"false", then Scan will	use eventually
	   consistent reads. The data returned from Scan might not contain the
	   results of other recently completed write operations	(PutItem,
	   UpdateItem or DeleteItem). The Scan response	might include some
	   stale data.

       o   If ConsistentRead is	"true",	then Scan will use strongly consistent
	   reads. All of the write operations that completed before the	Scan
	   began are guaranteed	to be contained	in the Scan response.

       The default setting for ConsistentRead is "false", meaning that
       eventually consistent reads will	be used.

       Strongly	consistent reads are not supported on global secondary
       indexes.	If you scan a global secondary index with ConsistentRead set
       to true,	you will receive a ValidationException.

   ExclusiveStartKey =>	Paws::DynamoDB::Key
       The primary key of the first item that this operation will evaluate.
       Use the value that was returned for LastEvaluatedKey in the previous
       operation.

       The data	type for ExclusiveStartKey must	be String, Number or Binary.
       No set data types are allowed.

       In a parallel scan, a Scan request that includes	ExclusiveStartKey must
       specify the same	segment	whose previous Scan returned the corresponding
       value of	LastEvaluatedKey.

   ExpressionAttributeNames => Paws::DynamoDB::ExpressionAttributeNameMap
       One or more substitution	tokens for attribute names in an expression.
       The following are some use cases	for using ExpressionAttributeNames:

       o   To access an	attribute whose	name conflicts with a DynamoDB
	   reserved word.

       o   To create a placeholder for repeating occurrences of	an attribute
	   name	in an expression.

       o   To prevent special characters in an attribute name from being
	   misinterpreted in an	expression.

       Use the name. For example, consider the following attribute name:

       o   "Percentile"

       The name	of this	attribute conflicts with a reserved word, so it	cannot
       be used directly	in an expression. (For the complete list of reserved
       words, see Reserved Words in the	Amazon DynamoDB	Developer Guide).  To
       work around this, you could specify the following for
       ExpressionAttributeNames:

       o   "{""

       You could then use this substitution in an expression, as in this
       example:

       o   ""

       Tokens that begin with the : character are expression attribute values,
       which are placeholders for the actual value at runtime.

       For more	information on expression attribute names, see Accessing Item
       Attributes in the Amazon	DynamoDB Developer Guide.

   ExpressionAttributeValues =>	Paws::DynamoDB::ExpressionAttributeValueMap
       One or more values that can be substituted in an	expression.

       Use the : (colon) character in an expression to dereference an
       attribute value.	For example, suppose that you wanted to	check whether
       the value of the	ProductStatus attribute	was one	of the following:

       "Available | Backordered	| Discontinued"

       You would first need to specify ExpressionAttributeValues as follows:

       "{ ":avail":{"S":"Available"}, ":back":{"S":"Backordered"},
       ":disc":{"S":"Discontinued"} }"

       You could then use these	values in an expression, such as this:

       "ProductStatus IN (:avail, :back, :disc)"

       For more	information on expression attribute values, see	Specifying
       Conditions in the Amazon	DynamoDB Developer Guide.

   FilterExpression => Str
       A string	that contains conditions that DynamoDB applies after the Scan
       operation, but before the data is returned to you. Items	that do	not
       satisfy the FilterExpression criteria are not returned.

       A FilterExpression is applied after the items have already been read;
       the process of filtering	does not consume any additional	read capacity
       units.

       For more	information, see Filter	Expressions in the Amazon DynamoDB
       Developer Guide.

       FilterExpression	replaces the legacy ScanFilter and ConditionalOperator
       parameters.

   IndexName =>	Str
       The name	of a secondary index to	scan. This index can be	any local
       secondary index or global secondary index. Note that if you use the
       "IndexName" parameter, you must also provide "TableName".

   Limit => Int
       The maximum number of items to evaluate (not necessarily	the number of
       matching	items).	If DynamoDB processes the number of items up to	the
       limit while processing the results, it stops the	operation and returns
       the matching values up to that point, and a key in LastEvaluatedKey to
       apply in	a subsequent operation,	so that	you can	pick up	where you left
       off. Also, if the processed data	set size exceeds 1 MB before DynamoDB
       reaches this limit, it stops the	operation and returns the matching
       values up to the	limit, and a key in LastEvaluatedKey to	apply in a
       subsequent operation to continue	the operation. For more	information,
       see Query and Scan in the Amazon	DynamoDB Developer Guide.

   ProjectionExpression	=> Str
       A string	that identifies	one or more attributes to retrieve from	the
       specified table or index. These attributes can include scalars, sets,
       or elements of a	JSON document. The attributes in the expression	must
       be separated by commas.

       If no attribute names are specified, then all attributes	will be
       returned. If any	of the requested attributes are	not found, they	will
       not appear in the result.

       For more	information, see Accessing Item	Attributes in the Amazon
       DynamoDB	Developer Guide.

       ProjectionExpression replaces the legacy	AttributesToGet	parameter.

   ReturnConsumedCapacity => Str
   ScanFilter => Paws::DynamoDB::FilterConditionMap
       This is a legacy	parameter, for backward	compatibility. New
       applications should use FilterExpression	instead. Do not	combine	legacy
       parameters and expression parameters in a single	API call; otherwise,
       DynamoDB	will return a ValidationException exception.

       A condition that	evaluates the scan results and returns only the
       desired values.

       This parameter does not support attributes of type List or Map.

       If you specify more than	one condition in the ScanFilter	map, then by
       default all of the conditions must evaluate to true. In other words,
       the conditions are ANDed	together. (You can use the ConditionalOperator
       parameter to OR the conditions instead. If you do this, then at least
       one of the conditions must evaluate to true, rather than	all of them.)

       Each ScanFilter element consists	of an attribute	name to	compare, along
       with the	following:

       o   AttributeValueList -	One or more values to evaluate against the
	   supplied attribute. The number of values in the list	depends	on the
	   operator specified in ComparisonOperator .

	   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

	   For Binary, DynamoDB	treats each byte of the	binary data as
	   unsigned when it compares binary values.

	   For information on specifying data types in JSON, see JSON Data
	   Format in the Amazon	DynamoDB Developer Guide.

       o   ComparisonOperator -	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"

	   For complete	descriptions of	all comparison operators, see
	   Condition.

   Segment => Int
       For a parallel Scan request, Segment identifies an individual segment
       to be scanned by	an application worker.

       Segment IDs are zero-based, so the first	segment	is always 0. For
       example,	if you want to use four	application threads to scan a table or
       an index, then the first	thread specifies a Segment value of 0, the
       second thread specifies 1, and so on.

       The value of LastEvaluatedKey returned from a parallel Scan request
       must be used as ExclusiveStartKey with the same segment ID in a
       subsequent Scan operation.

       The value for Segment must be greater than or equal to 0, and less than
       the value provided for TotalSegments.

       If you provide Segment, you must	also provide TotalSegments.

   Select => Str
       The attributes to be returned in	the result. You	can retrieve all item
       attributes, specific item attributes, or	the count of matching items.

       o   "ALL_ATTRIBUTES" - Returns all of the item attributes.

       o   "COUNT" - Returns the number	of matching items, rather than the
	   matching items themselves.

       o   "SPECIFIC_ATTRIBUTES" - Returns only	the attributes listed in
	   AttributesToGet. This return	value is equivalent to specifying
	   AttributesToGet without specifying any value	for Select.

       If neither Select nor AttributesToGet are specified, DynamoDB defaults
       to "ALL_ATTRIBUTES". You	cannot use both	AttributesToGet	and Select
       together	in a single request, unless the	value for Select is
       "SPECIFIC_ATTRIBUTES". (This usage is equivalent	to specifying
       AttributesToGet without any value for Select.)

   REQUIRED TableName => Str
       The name	of the table containing	the requested items; or, if you
       provide "IndexName", the	name of	the table to which that	index belongs.

   TotalSegments => Int
       For a parallel Scan request, TotalSegments represents the total number
       of segments into	which the Scan operation will be divided.  The value
       of TotalSegments	corresponds to the number of application workers that
       will perform the	parallel scan. For example, if you want	to use four
       application threads to scan a table or an index,	specify	a
       TotalSegments value of 4.

       The value for TotalSegments must	be greater than	or equal to 1, and
       less than or equal to 1000000. If you specify a TotalSegments value of
       1, the Scan operation will be sequential	rather than parallel.

       If you specify TotalSegments, you must also specify Segment.

SEE ALSO
       This class forms	part of	Paws, documenting arguments for	method Scan in
       Paws::DynamoDB

BUGS and CONTRIBUTIONS
       The source code is located here:	https://github.com/pplu/aws-sdk-perl

       Please report bugs to: https://github.com/pplu/aws-sdk-perl/issues

POD ERRORS
       Hey! The	above document had some	coding errors, which are explained
       below:

       Around line 211:
	   Unterminated	B<...> sequence

       Around line 230:
	   Unterminated	C<...> sequence

       Around line 241:
	   Unterminated	C<...> sequence

perl v5.24.1			  2015-08-06	       Paws::DynamoDB::Scan(3)

NAME | DESCRIPTION | ATTRIBUTES | SEE ALSO | BUGS and CONTRIBUTIONS | POD ERRORS

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