Retrieving Multiple Columns
To retrieve multiple columns from a table, the same SELECT statement is used. The only difference is that multiple column names must be specified after the SELECT keyword, and each column must be separated by a comma.
Tip
Take Care with Commas When selecting multiple columns, be sure to specify a comma between each column name, but not after the last column name. Doing so will generate an error.
The following SELECT statement retrieves three columns from the products table:
• Input
SELECT prod_id, prod_name, prod_price
FROM products;
• Analysis
Just as in the prior example, this statement uses the SELECT statement to retrieve data from the products table. In this example, three column names are specified, each separated by a comma. The output from this statement is as follows:
• Output
+---------+----------------+------------+
| prod_id | prod_name | prod_price |
+---------+----------------+------------+
| ANV01 | .5 ton anvil | 5.99 |
| ANV02 | 1 ton anvil | 9.99 |
| ANV03 | 2 ton anvil | 14.99 |
| OL1 | Oil can | 8.99 |
| FU1 | Fuses | 3.42 |
| SLING | Sling | 4.49 |
| TNT1 | TNT (1 stick) | 2.50 |
| TNT2 | TNT (5 sticks) | 10.00 |
| FB | Bird seed | 10.00 |
| FC | Carrots | 2.50 |
| SAFE | Safe | 50.00 |
| DTNTR | Detonator | 13.00 |
| JP1000 | JetPack 1000 | 35.00 |
| JP2000 | JetPack 2000 | 55.00 |
+---------+----------------+------------+
Note
Presentation of Data SQL statements typically return raw, unformatted data. Data formatting is a presentation issue, not a retrieval issue. Therefore, presentation (for example, alignment and displaying the price values as currency amounts with the currency symbol and commas) is typically specified in the application that displays the data. Actual raw retrieved data (without application-provided formatting) is rarely displayed as is.
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