AWS Tools for Windows PowerShell
Command Reference

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Synopsis

Calls the Amazon DynamoDB UpdateItem API operation.

Syntax

Update-DDBItem
-Key <Hashtable>
-AttributeUpdate <Hashtable>
-ConditionalOperator <ConditionalOperator>
-ConditionExpression <String>
-Expected <Hashtable>
-ExpressionAttributeName <Hashtable>
-ExpressionAttributeValue <Hashtable>
-ReturnConsumedCapacity <ReturnConsumedCapacity>
-ReturnItemCollectionMetric <ReturnItemCollectionMetrics>
-ReturnValue <ReturnValue>
-ReturnValuesOnConditionCheckFailure <ReturnValuesOnConditionCheckFailure>
-TableName <String>
-UpdateExpression <String>
-Select <String>
-PassThru <SwitchParameter>
-Force <SwitchParameter>
-ClientConfig <AmazonDynamoDBConfig>

Description

Edits an existing item's attributes, or adds a new item to the table if it does not already exist. You can put, delete, or add attribute values. You can also perform a conditional update on an existing item (insert a new attribute name-value pair if it doesn't exist, or replace an existing name-value pair if it has certain expected attribute values). You can also return the item's attribute values in the same UpdateItem operation using the ReturnValues parameter.

Parameters

-AttributeUpdate <Hashtable>
This is a legacy parameter. Use UpdateExpression instead. For more information, see AttributeUpdates in the Amazon DynamoDB Developer Guide.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
AliasesAttributeUpdates
-ClientConfig <AmazonDynamoDBConfig>
Amazon.PowerShell.Cmdlets.DDB.AmazonDynamoDBClientCmdlet.ClientConfig
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
-ConditionalOperator <ConditionalOperator>
This is a legacy parameter. Use ConditionExpression instead. For more information, see ConditionalOperator in the Amazon DynamoDB Developer Guide.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
-ConditionExpression <String>
A condition that must be satisfied in order for a conditional update to succeed.An expression can contain any of the following:
  • Functions: attribute_exists | attribute_not_exists | attribute_type | contains | begins_with | sizeThese function names are case-sensitive.
  • Comparison operators: = | <> | < | > | <= | >= | BETWEEN | IN
  • Logical operators: AND | OR | NOT
For more information about condition expressions, see Specifying Conditions in the Amazon DynamoDB Developer Guide.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
-Expected <Hashtable>
This is a legacy parameter. Use ConditionExpression instead. For more information, see Expected in the Amazon DynamoDB Developer Guide.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
-ExpressionAttributeName <Hashtable>
One or more substitution tokens for attribute names in an expression. The following are some use cases for using ExpressionAttributeNames:
  • To access an attribute whose name conflicts with a DynamoDB reserved word.
  • To create a placeholder for repeating occurrences of an attribute name in an expression.
  • To prevent special characters in an attribute name from being misinterpreted in an expression.
Use the # character in an expression to dereference an attribute name. For example, consider the following attribute name:
  • 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:
  • {"#P":"Percentile"}
You could then use this substitution in an expression, as in this example:
  • #P = :val
Tokens that begin with the : character are expression attribute values, which are placeholders for the actual value at runtime.For more information about expression attribute names, see Specifying Item Attributes in the Amazon DynamoDB Developer Guide.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
AliasesExpressionAttributeNames
-ExpressionAttributeValue <Hashtable>
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 | DiscontinuedYou 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 Condition Expressions in the Amazon DynamoDB Developer Guide.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
AliasesExpressionAttributeValues
This parameter overrides confirmation prompts to force the cmdlet to continue its operation. This parameter should always be used with caution.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
-Key <Hashtable>
The primary key of the item to be updated. Each element consists of an attribute name and a value for that attribute.For the primary key, you must provide all of the attributes. For example, with a simple primary key, you only need to provide a value for the partition key. For a composite primary key, you must provide values for both the partition key and the sort key.
Required?True
Position?1
Accept pipeline input?True (ByValue, ByPropertyName)
-PassThru <SwitchParameter>
Changes the cmdlet behavior to return the value passed to the Key parameter. The -PassThru parameter is deprecated, use -Select '^Key' instead. This parameter will be removed in a future version.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
-ReturnConsumedCapacity <ReturnConsumedCapacity>
The service has not provided documentation for this parameter; please refer to the service's API reference documentation for the latest available information.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
-ReturnItemCollectionMetric <ReturnItemCollectionMetrics>
Determines whether item collection metrics are returned. If set to SIZE, the response includes statistics about item collections, if any, that were modified during the operation are returned in the response. If set to NONE (the default), no statistics are returned.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
AliasesReturnItemCollectionMetrics
-ReturnValue <ReturnValue>
Use ReturnValues if you want to get the item attributes as they appear before or after they are successfully updated. For UpdateItem, the valid values are:
  • NONE - If ReturnValues is not specified, or if its value is NONE, then nothing is returned. (This setting is the default for ReturnValues.)
  • ALL_OLD - Returns all of the attributes of the item, as they appeared before the UpdateItem operation.
  • UPDATED_OLD - Returns only the updated attributes, as they appeared before the UpdateItem operation.
  • ALL_NEW - Returns all of the attributes of the item, as they appear after the UpdateItem operation.
  • UPDATED_NEW - Returns only the updated attributes, as they appear after the UpdateItem operation.
There is no additional cost associated with requesting a return value aside from the small network and processing overhead of receiving a larger response. No read capacity units are consumed.The values returned are strongly consistent.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
AliasesReturnValues
-ReturnValuesOnConditionCheckFailure <ReturnValuesOnConditionCheckFailure>
An optional parameter that returns the item attributes for an UpdateItem operation that failed a condition check.There is no additional cost associated with requesting a return value aside from the small network and processing overhead of receiving a larger response. No read capacity units are consumed.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
-Select <String>
Use the -Select parameter to control the cmdlet output. The default value is 'Attributes'. Specifying -Select '*' will result in the cmdlet returning the whole service response (Amazon.DynamoDBv2.Model.UpdateItemResponse). Specifying the name of a property of type Amazon.DynamoDBv2.Model.UpdateItemResponse will result in that property being returned. Specifying -Select '^ParameterName' will result in the cmdlet returning the selected cmdlet parameter value.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
-TableName <String>
The name of the table containing the item to update. You can also provide the Amazon Resource Name (ARN) of the table in this parameter.
Required?True
Position?Named
Accept pipeline input?True (ByPropertyName)
-UpdateExpression <String>
An expression that defines one or more attributes to be updated, the action to be performed on them, and new values for them.The following action values are available for UpdateExpression.
  • SET - Adds one or more attributes and values to an item. If any of these attributes already exist, they are replaced by the new values. You can also use SET to add or subtract from an attribute that is of type Number. For example: SET myNum = myNum + :valSET supports the following functions:
    • if_not_exists (path, operand) - if the item does not contain an attribute at the specified path, then if_not_exists evaluates to operand; otherwise, it evaluates to path. You can use this function to avoid overwriting an attribute that may already be present in the item.
    • list_append (operand, operand) - evaluates to a list with a new element added to it. You can append the new element to the start or the end of the list by reversing the order of the operands.
    These function names are case-sensitive.
  • REMOVE - Removes one or more attributes from an item.
  • ADD - Adds the specified value to the item, if the attribute does not already exist. If the attribute does exist, then the behavior of ADD depends on the data type of the attribute:
    • If the existing attribute is a number, and if Value is also a number, then Value is mathematically added to the existing attribute. If Value is a negative number, then it is subtracted from the existing attribute.If you use ADD to increment or decrement a number value for an item that doesn't exist before the update, DynamoDB uses 0 as the initial value.Similarly, if you use ADD for an existing item to increment or decrement an attribute value that doesn't exist before the update, DynamoDB uses 0 as the initial value. For example, suppose that the item you want to update doesn't have an attribute named itemcount, but you decide to ADD the number 3 to this attribute anyway. DynamoDB will create the itemcount attribute, set its initial value to 0, and finally add 3 to it. The result will be a new itemcount attribute in the item, with a value of 3.
    • If the existing data type is a set and if Value is also a set, then Value is added to the existing set. For example, if the attribute value is the set [1,2], and the ADD action specified [3], then the final attribute value is [1,2,3]. An error occurs if an ADD action is specified for a set attribute and the attribute type specified does not match the existing set type. Both sets must have the same primitive data type. For example, if the existing data type is a set of strings, the Value must also be a set of strings.
    The ADD action only supports Number and set data types. In addition, ADD can only be used on top-level attributes, not nested attributes.
  • DELETE - Deletes an element from a set.If a set of values is specified, then those values are subtracted from the old set. For example, if the attribute value was the set [a,b,c] and the DELETE action specifies [a,c], then the final attribute value is [b]. Specifying an empty set is an error.The DELETE action only supports set data types. In addition, DELETE can only be used on top-level attributes, not nested attributes.
You can have many actions in a single expression, such as the following: SET a=:value1, b=:value2 DELETE :value3, :value4, :value5For more information on update expressions, see Modifying Items and Attributes in the Amazon DynamoDB Developer Guide.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)

Common Credential and Region Parameters

-AccessKey <String>
The AWS access key for the user account. This can be a temporary access key if the corresponding session token is supplied to the -SessionToken parameter.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
AliasesAK
-Credential <AWSCredentials>
An AWSCredentials object instance containing access and secret key information, and optionally a token for session-based credentials.
Required?False
Position?Named
Accept pipeline input?True (ByValue, ByPropertyName)
-EndpointUrl <String>
The endpoint to make the call against.Note: This parameter is primarily for internal AWS use and is not required/should not be specified for normal usage. The cmdlets normally determine which endpoint to call based on the region specified to the -Region parameter or set as default in the shell (via Set-DefaultAWSRegion). Only specify this parameter if you must direct the call to a specific custom endpoint.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
-NetworkCredential <PSCredential>
Used with SAML-based authentication when ProfileName references a SAML role profile. Contains the network credentials to be supplied during authentication with the configured identity provider's endpoint. This parameter is not required if the user's default network identity can or should be used during authentication.
Required?False
Position?Named
Accept pipeline input?True (ByValue, ByPropertyName)
-ProfileLocation <String>
Used to specify the name and location of the ini-format credential file (shared with the AWS CLI and other AWS SDKs)If this optional parameter is omitted this cmdlet will search the encrypted credential file used by the AWS SDK for .NET and AWS Toolkit for Visual Studio first. If the profile is not found then the cmdlet will search in the ini-format credential file at the default location: (user's home directory)\.aws\credentials.If this parameter is specified then this cmdlet will only search the ini-format credential file at the location given.As the current folder can vary in a shell or during script execution it is advised that you use specify a fully qualified path instead of a relative path.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
AliasesAWSProfilesLocation, ProfilesLocation
-ProfileName <String>
The user-defined name of an AWS credentials or SAML-based role profile containing credential information. The profile is expected to be found in the secure credential file shared with the AWS SDK for .NET and AWS Toolkit for Visual Studio. You can also specify the name of a profile stored in the .ini-format credential file used with the AWS CLI and other AWS SDKs.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
AliasesStoredCredentials, AWSProfileName
-Region <Object>
The system name of an AWS region or an AWSRegion instance. This governs the endpoint that will be used when calling service operations. Note that the AWS resources referenced in a call are usually region-specific.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
AliasesRegionToCall
-SecretKey <String>
The AWS secret key for the user account. This can be a temporary secret key if the corresponding session token is supplied to the -SessionToken parameter.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
AliasesSK, SecretAccessKey
-SessionToken <String>
The session token if the access and secret keys are temporary session-based credentials.
Required?False
Position?Named
Accept pipeline input?True (ByPropertyName)
AliasesST

Outputs

This cmdlet returns a collection of System.String objects. The service call response (type Amazon.DynamoDBv2.Model.UpdateItemResponse) can also be referenced from properties attached to the cmdlet entry in the $AWSHistory stack.

Examples

Example 1

$key = @{
SongTitle = 'Somewhere Down The Road'
Artist = 'No One You Know'
} | ConvertTo-DDBItem

$updateDdbItem = @{
TableName = 'Music'
Key = $key
UpdateExpression = 'set Genre = :val1'
ExpressionAttributeValue = (@{
':val1' = ([Amazon.DynamoDBv2.Model.AttributeValue]'Rap')
})
}
Update-DDBItem @updateDdbItem

Name Value
---- -----
Genre Rap
Sets the genre attribute to 'Rap' on the DynamoDB item with the partition key SongTitle and the sort key Artist.

Supported Version

AWS Tools for PowerShell: 2.x.y.z