Bewilderedly behold this SQL statement:
SELECT * FROM a.b.c;
Nobody can know the meaning of "a.b.c" without knowing the terminology, the context, and the varying intents of various DBMS implementors.
It's pretty clear that a.b.c is a name, that is, a unique reference to an SQL object, which in this case is a table.
The name happens to be qualified -- it has three parts separated by periods. A generalist would say that each part is a container, with the first part referring to the outermost container a, which contains b, which contains c. Analogies would be: a directory with a subdirectory and a sub-subdirectory, …[Read more...]