Limit Default - forcing bad behavior on servers

[troydavisson]

Limit Default - forcing bad behavior on servers

[troydavisson]

Were you running into this doing KeyIndex-type queries or with any normal type of query? Something sounds off with those servers. Not including the Limit parameter shouldn't ever do more for you than providing Limit=99999999. The other thing that should be better than providing Limit=99999999 is Limit=NONE when doing KeyIndex queries.

If this entry is set to a number greater than zero, the server MUST not return
more than the specified number of records. If the request results in more
matches than the server returns, the tag MUST be sent at
the end of the data stream, regardless of any Limit parameter specified in
the client request.

In general, if this entry is set to (“NONE”) or is not present, the server SHOULD
treat this as a request to suspend enforcement of any internal download limit.
Servers that permit the suspension of the limit MUST disable both the
tag and the return code 20208, Maximum Records Exceeded
when responding to a Limit=”NONE” request. Servers that do not permit the
suspension of the limit MUST apply the and return code 20208
in the cases where the query results in more rows than permitted. Client
implementers should be aware that some server implementations might not
honor the request to disable the limit or may restrict the request to the selection
of certain fields as described below; the server operator’s business rules take
precedence over the request to waive the system download limit.

A server may only support the suspension of the limit for a certain scenario of
requests. When a server has Classes with a HasKeyIndex value of TRUE in
the Class Metadata the server MUST suspend enforcement of the download
limit for such a Class when the Limit=”NONE” and the Select argument contains
only field names that have the InKeyIndex value of TRUE in the Table Metadata.
A server SHOULD support HasKeyIndex for each Class and MUST have the
InKeyField value of TRUE for at least the KeyField of the Class when the
HasKeyIndex is TRUE for that Class. A server MAY have more than one field
with the InKeyField value of TRUE for any Class.

Any request that sets a numeric Limit disables support for unlimited key index
results as described in section 7.4.5 Select.

from: http://retsdoc.onconfluence.com/display/rets172/7.4+Optional+Request+Arguments

The 99999999 is used by default to get around an ambiguity in the spec. According to the RETS spec, using "NONE" or not providing one is something that should be treated by the server as a request to suspend limit enforcement. By providing the large number, you're essentially making the same request but leaving less up to interpretation by not counting on a non-MUST in the spec.

http://forums.rets.org/showthread.php?t=544