Yes, this is correct. But the thing is that I don't want to find out how
a certain query is processed but instead how the processing is done when
the query type is determined by the join optimizer. When the optimizer has
decided to do a full table scan, does it do it as a nested loop join, a
b
That is why you need to use the EXPLAIN command. As I understand it, MySQL
has a number of different ways of doing a JOIN, and it attempts to optimise
those dynamically by inspecting not only which indexes it has available but
the sizes of the tables involved (e.g. to try to use the brute-force s
I am interested in the internal join algorithms, not the join types that
can be found in the manual. My question is how the join types in the
manual are processed internally? Or, what are the different join
algorithms supported by MySQL?
> It depends on your database & query structure and es
It depends on your database & query structure and especially what
indexes are available. If you just put "explain" in front of your query
you will be able to see how mysql will execute your query.
On Tuesday, September 10, 2002, at 09:45 AM, Toni Strandell wrote:
>
> How does MySQL process a j
How does MySQL process a join between tables? Does it always use
nested-loop join, or does it use sort-merge join if the table is sorted
before joining it? Is the join algorithm merge if the tables are already
sorted on the join attributes (through an index)?
Sincerely,
Toni Strandell
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