The lookup table feature is best suited for static, small tables.
A lookup table functions in the following manner:
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A target column can have only one lookup table associated with it.
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If the lookup table is deleted or the unique key index is dropped, the request is terminated, and an alert is generated.
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After the initial Copy is completed, only changes in the trigger table can trigger updates, deletes, and inserts. The trigger table is the sending table whose row triggers replication.
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Lookup tables are available for all database platforms supported in the current version of the model.
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A lookup table must have a single column that forms a unique key on which to perform a lookup from the trigger table.
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A lookup table must be located within the same database and same server as the associated source table. On those platforms that may have multiple databases on a single server (MS SQL Server, Sybase, and Informix), table lookups may not be performed between databases.
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Use only the character datatype for the columns you wish to return from lookup tables. To use a lookup table with another datatype, you must first convert the datatype in the expression you write, using one of the built-in conversions such as Numeric to character. Similarly, if you need the value that is returned to be a different datatype, you can convert it, using built-in conversion methods such as Character to numeric decimal, Character to numeric double, or Character to numeric integer.