Database Reference
In-Depth Information
•
ALL_PROJECTED_ATTRIBUTES
: This returns all the item attributes from the
index and does not apply to the table. If all the table attributes are projected into
the secondary index, then
ALL_PROJECTED_ATTRIBUTES
will function in the
same way as
ALL_ATTRIBUTES
.
•
SPECIFIC_ATTRIBUTES
: This returns the attributes specified in the
At-
tributesToGet
list, which is the sixth parameter in our
QueryRequest
.
•
COUNT
: This returns the number of matching items.
The sixth parameter (as discussed) takes
String[]
or
List<String>
with the attrib-
ute names that are to be retrieved by the query operation. The seventh parameter limits the
number of items to be retrieved by the query. This is usually used along with the exclusive
start key (which we will discuss later). The last parameter is used to specify whether the
read has to be strongly consistent.
