What Are Indexes Used For?

1.	What Are Indexes Used For?
Answer» Indexes enable faster access to the ROWS of a table. You can build indexes for a single column or for a SEQUENCE of COLUMNS. The definition of indexes determines whether the column value of DIFFERENT rows in the indexed columns must be UNIQUE or not (UNIQUE or NON-UNIQUE index). An assigned index name and the table names must be unique. Therefore, there can be several indexes with the same name for each database user or scheme, but not for the same table.

Answer»

Indexes enable faster access to the ROWS of a table.
You can build indexes for a single column or for a SEQUENCE of COLUMNS.
The definition of indexes determines whether the column value of DIFFERENT rows in the indexed columns must be UNIQUE or not (UNIQUE or NON-UNIQUE index).
An assigned index name and the table names must be unique. Therefore, there can be several indexes with the same name for each database user or scheme, but not for the same table.

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