my question is , when I create an index for a table in mysql, I see that the index_type is type BTREE
. Now although I understand about btree(s), I do not quiet understand how it stores the index and how the database searches the records based on this.
I mean, btree is excellent for databases to perform read and writes large blocks of data,
when we create an index for column type of Primary key
, what I understand is, it creates a tree and splitting the values for the root based on the value type of the root.
Now, does it store only the the primary key ID
under the trees or the whole data associoated with that primary key?
after finding the wanted primary ID, how does the database extract the record?
Hope I am clear.
Thanks.