RETS Search Transaction Reply Codes

During working on RETS Server lots of time I got some error code and I thought to have the meaning of those code. At last I found those code and their meaning in the following location..

https://retsdoc.atlassian.net/wiki/display/rets172/7.8+Reply+Codes

I am also adding those code and their meaning right here

Reply Code	Meaning
0	Operation successful.
20200	Unknown Query Field  The query could not be understood due to an unknown field name.
20201	No Records Found  No matching records were found.
20202	Invalid Select  The Select statement contains field names that are not recognized by the server.
20203	Miscellaneous Search Error  The quoted-string of the body-start-line contains text that MAY be displayed to the user.
20206	Invalid Query Syntax  The query could not be understood due to a syntax error.
20207	Unauthorized Query  The query could not be executed because it refers to a field to which the supplied login does not grant access.
20208	Maximum Records Exceeded  Operation successful, but all of the records have not been returned. This reply code indicates that the maximum records allowed to be returned by the server have been exceeded. Note: reaching/exceeding the "Limit" value in the client request is not a cause for the server to generate this error.
20209	Timeout  The request timed out while executing
20210	Too many outstanding queries  The user has too many outstanding queries and new queries will not be accepted at this time.
20211	Query too complex  The query is too complex to be processed. For example, the query contains too many nesting levels or too many values for a lookup field.
20212	Invalid key request  The transaction does not meet the server's requirements for the use of the Key option.
20213	Invalid Key  The transaction uses a key that is incorrect or is no longer valid. Servers are not required to detect all possible invalid key values.
20514	Requested DTD version unavailable.  The client has requested the metadata in STANDARD-XML format using a DTD version that the server cannot provide.