CHAPTER 2
B-tree Indexes
The B-tree index is the default index type in Oracle. This index type is known as B-tree because the table row identifier (ROWID) and associated column values are stored within index blocks in a balanced tree-like structure. Oracle B-tree indexes are used for the following reasons:
- Improving SQL statement performance.
- Enforcing uniqueness of primary key and unique key constraints.
- Reducing potential locking issues with parent and child table tables associated via primary and foreign key constraints.
If a table column value (or combination of columns) is fairly unique within all rows in a table, then creating a B-tree ...
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