Thread: Can we add syntax for references auto create index or not.
When we create table, some column use foreign key references.
Now PostgreSQL don't create index for the FK, and there is no problem.
But when some body need the index to speed up the query within these APP, they need to add the index manual one-by-one when has many tables.
If we can add syntax for auto create index for FK by user's choose, and default not create?
When we create table, some column use foreign key references.Now PostgreSQL don't create index for the FK, and there is no problem.But when some body need the index to speed up the query within these APP, they need to add the index manual one-by-one when has many tables.If we can add syntax for auto create index for FK by user's choose, and default not create?
I presume you mean to modify the CREATE TABLE statement.
How does this help solve the problem "when some body need the index to speed up the query"?
My first impression is that I like the idea. The fact that it is not supported by the SQL standard is a drawback Do any other vendors do this?
David J.
On Wednesday, May 27, 2015, digoal zhou <digoal.zhou@gmail.com> wrote:
2015-05-28 1:41 GMT+08:00 David G. Johnston <david.g.johnston@gmail.com>:When we create table, some column use foreign key references.Now PostgreSQL don't create index for the FK, and there is no problem.But when some body need the index to speed up the query within these APP, they need to add the index manual one-by-one when has many tables.If we can add syntax for auto create index for FK by user's choose, and default not create?I presume you mean to modify the CREATE TABLE statement.How does this help solve the problem "when some body need the index to speed up the query"?Sometimes, when user need delete FK's parent table's tuple, FK has an index will improve the performance.or sometime, user need query FK table with FK's condition (assume it need the btree index).
I understand why one would want a FK but if they actually thought they would need it they would have issued a create index at the same time (well, just after) they create the table. Seeing a poorly performing query and going, "crap, I forgot the index" isn't solved by this though it may make the need more obvious while the user is writing the create table in the first place.
There is no other database product do the thing, but if PG has the syntax(when add FK, user can choose whether or not create index), users will happy to use it.
Are you asking if such a featured would be accepted or pleading for someone to code it?
David J.
2015-05-28 1:41 GMT+08:00 David G. Johnston <david.g.johnston@gmail.com>:
When we create table, some column use foreign key references.Now PostgreSQL don't create index for the FK, and there is no problem.But when some body need the index to speed up the query within these APP, they need to add the index manual one-by-one when has many tables.If we can add syntax for auto create index for FK by user's choose, and default not create?I presume you mean to modify the CREATE TABLE statement.How does this help solve the problem "when some body need the index to speed up the query"?
Sometimes, when user need delete FK's parent table's tuple, FK has an index will improve the performance.
or sometime, user need query FK table with FK's condition (assume it need the btree index).
There is no other database product do the thing, but if PG has the syntax(when add FK, user can choose whether or not create index), users will happy to use it.
Regards,
digoal
My first impression is that I like the idea. The fact that it is not supported by the SQL standard is a drawback Do any other vendors do this?David J.