Which RDMS are you using. In SQL Server, TOP only works with SQL 7 compatible databases are higher. If you are using SQL Server, check the compatibility level of the database that doesn't work with TOP.
sp_dbcmptlevel 'dbname' will check the compatibility level. sp_dbcmptlevel 'dbname' 70 will set the level to 7. Changing the compatibility level will alter other behviors in sql server so be cautious. You can change the compatibility level for the query and then change it back after the query. For example, ...
sp_dbcmptlevel 'dbname' 70
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Select top ....
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sp_dbcmptlevel 'dbname' 65
Go Terry Broadbent
Please review faq183-874.
"The greatest obstacle to discovery is not ignorance -- it is the illusion of knowledge." - Daniel J Boorstin