How Can I Efficiently Select All Columns Plus a Row Number in Oracle SQL?

Rownum and the Mystery of the '*'

In the realm of Oracle database querying, selecting all columns from a table is a common task. However, what if you also wish to include additional columns, such as the row number, without the tedious process of manually listing each column?

Consider the following scenario: you have a table with multiple columns and you want to retrieve all the data, including the row number as an extra column. The traditional approach would be to specify each column explicitly, as seen below:

SELECT rownum, column1, column2 FROM table

While this method works, it can become cumbersome and inefficient when dealing with large tables. Instead, let's unlock the secret of the '*' symbol.

Qualifying the '*' with the table name allows you to select all its columns in a single, concise expression:

SELECT rownum, table.* FROM table

With this approach, you can effortlessly retrieve all columns, including the row number, without resorting to manual enumeration.

To illustrate, let's apply this solution to the example table:

rownum       column1       column2       column3       column4
1            Joe           Smith         1             2
2            Bob           Jones         3             4

Using the qualified '*' expression, we obtain the desired result set, saving both time and effort.

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