Sergei, On Wed, Sep 1, 2021 at 10:13 PM Sergei Golubchik <serg@mariadb.org> wrote:
Hi, Aleksey!
On Sep 01, Aleksey Midenkov wrote:
+move_out_partition: + MIGRATE_SYM PARTITION_SYM + | MIGRATE_SYM OUT_SYM PARTITION_SYM
Where does this OUT_SYM came out from? It doesn't add any values, it doesn't make the syntax more natural. Why did you add it?
I think that helps to make syntax more natural if we do MIGRATE PARTITION in both directions. If it is written MIGRATE OUT or MIGRATE IN that is easier to understand what's going on. FROM/TO in the end is not helping much because it is harder to notice. Partition specification presence or absence: not so explicit to understand quickly.
It incorrect English. And it's a noise word that adds no value and doesn't make anything easier to understand.
MIGRATE PARTITION x TO TABLE y
is correct and unambigous although not a very traditional use of the word "migrate". MIGRATE OUT PARTITION x TO TABLE y is just wrong.
If there is "move in" and "move out", "migrate in" and "migrate out" cannot be wrong. Look for examples for "migrate out to" and "migrate in from".
+ ; + +to_table: + TO_SYM TABLE_SYM + | TO_SYM
Let's keep the TABLE_SYM. Saying
MIGRATE PARTITION p1 TO p2
is very vague, the syntax should explicitly say that it migrates a PARTITION to a TABLE. The statement mentions many different types of objects, if should be clear about what object type every identifier refers to.
That is a shortcut for easier typing and that is precious for command-line work! If some names can make misunderstanding one can always write
MIGRATE PARTITION p1 TO TABLE p2
Please do not restrict user freedom to choose between verbosity and brevity. I guess you have a preference for perl over python (and the democracy over dictatorship).
I do. But it's SQL, not perl. SQL is very verbose even when it isn't really justified. And here is is justified, so let's keep the syntax unambigous.
And why this is good and should be followed? There are shortcuts in SQL too. Okay, let's keep this unambiguous for a while.
Regards, Sergei VP of MariaDB Server Engineering and security@mariadb.org
-- All the best, Aleksey Midenkov @midenok