The result returned is non-deterministic

Error constant SQLE_NONDETERMINISTIC_RESULT
ODBC 2 State 01000
ODBC 3 State 01000
Severity 10
SQLCODE 122
SQLSTATE 01W18
Sybase error code 13883
Probable cause

FIRST or TOP n are used in a SELECT statement to limit the size of a result. The statement must also have an ORDER BY if the result is to be well-defined. If it does not have an ORDER BY, then the server is free to return any subset of the result that has the requested number of rows.