Using the EXISTS function with PartiQL for DynamoDB
You can use EXISTS to perform the same function as ConditionCheck
does in
the TransactWriteItems API. The EXISTS function can only be used in
transactions.
Given a value, returns TRUE
if the value is a non-empty collection.
Otherwise, returns FALSE
.
Note
This function can only be used in transactional operations.
Syntax
EXISTS (
statement
)
Arguments
statement
-
(Required) The SELECT statement that the function evaluates.
Note
The SELECT statement must specify a full primary key and one other condition.
Return type
bool
Examples
EXISTS( SELECT * FROM "Music" WHERE "Artist" = 'Acme Band' AND "SongTitle" = 'PartiQL Rocks')