Creates a new item, or replaces an old item with a new item
Creates a new item, or replaces an old item with a new item
Creates a new item, or replaces an old item with a new item. If an item that has the same primary key as the new item already exists in the specified table, the new item completely replaces the existing item. You can perform a conditional put operation (add a new item if one with the specified primary key doesn't exist), or replace an existing item if it has certain attribute values. You can return the item's attribute values in the same operation, using the ReturnValues parameter.
TableName: [required] The name of the table to contain the item. You can also provide the Amazon Resource Name (ARN) of the table in this parameter.
Item: [required] A map of attribute name/value pairs, one for each attribute. Only the primary key attributes are required; you can optionally provide other attribute name-value pairs for the item.
You must provide all of the attributes for the primary key. 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 both values for both the partition key and the sort key.
If you specify any attributes that are part of an index key, then the data types for those attributes must match those of the schema in the table's attribute definition.
Empty String and Binary attribute values are allowed. Attribute values of type String and Binary must have a length greater than zero if the attribute is used as a key attribute for a table or index.
For more information about primary keys, see Primary Key
in the Amazon DynamoDB Developer Guide.
Each element in the Item map is an AttributeValue object.
Expected: This is a legacy parameter. Use ConditionExpression instead. For more information, see Expected
in the Amazon DynamoDB Developer Guide.
ReturnValues: Use ReturnValues if you want to get the item attributes as they appeared before they were updated with the put_item request. For put_item, 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 - If put_item overwrote an attribute name-value pair, then the content of the old item is returned.
The values returned are strongly consistent.
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 ReturnValues parameter is used by several DynamoDB operations; however, put_item does not recognize any values other than NONE or ALL_OLD.
ReturnConsumedCapacity:
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.
ConditionalOperator: This is a legacy parameter. Use ConditionExpression instead. For more information, see ConditionalOperator
in the Amazon DynamoDB Developer Guide.
ConditionExpression: A condition that must be satisfied in order for a conditional put_item operation to succeed.
ExpressionAttributeNames: 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.
ExpressionAttributeValues: 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:
ReturnValuesOnConditionCheckFailure: An optional parameter that returns the item attributes for a put_item 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.