Hi All ,
I am having clarification on how index are stored .
I keep on reading that B-tree unique index are stored in sorted order( default ascending )
Indexes can be unique or nonunique. Unique indexes guarantee that no two rows of a table have duplicate values in the key column or columns. For example, no two employees can have the same employee ID. Thus, in a unique index, one rowid exists for each data value. The data in the leaf blocks is sorted only by key.
Question:
User "A" insert into a table with 1,3,5( My understanding is B-tree index is created with Root Block--->Branch Block-->Leaf Block for storing 1,3,5 in aceding order )
User "B" insert into a table with 2,3,6
(
-- Now the questin is how the index are stored in asceding order
--is there any operation happening inisde the b-tree index so that the Leaf block is rebuilded
-- or is there any different way the leaf block is created
)
create table test_index (a number primary key );
desc desc test_index;
desc test_index
Name Null Type
---- -------- ------
A NOT NULL NUMBER
INDEX_NAME UNIQUENESS
------------------------------ ----------
SYS_C00413788 UNIQUE
-- User A tries to insert 1 ,3 , 5
insert into test_index values (1);
insert into test_index values (3);
insert into test_index values (5);
commit;
-- My understanding is B-tree index is created with Root Block--->Branch Block-->Leaf Block for storing 1,3,5 in aceding order
-- User B tries to insert 2 ,4 , 6
insert into test_index values (2);
insert into test_index values (4);
insert into test_index values (6);
commit;
-- Now the questin is how the index are stored in asceding order
--is there any operation happening inisde the b-tree index so that the Leaf block is rebuilded
-- or is there any different way the leaf block is created