Answer Posted / tdguy
If a table in a database either has no natural key or the
natural key is so long that using it as the key would be
inefficient then we need to consider using a pseudokey
instead. Pseudokeys are usually given the same name as the
table they belong to with _id added to the end of the name.
They usually are defined to contain a number and use
autoincrement in mySQL or the equivalent in other versions
of SQL to dynamically allocate a value when new rows are
created.
source: http://www.felgall.com/mysql04.htm
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