Perl Programming Page 4 - Creating a Database with Perl and DBI |
The SELECT command allows us to query the database, and it reports back to us the information that matches the criteria we specify from the table we indicate. We have seen severalSELECTcommands in this form: mysql> SELECT * FROM musicians; player_id name phone 1 Roger Waters 555-1212 2 Geddy Lee 555-2323 3 Marshall Mathers III 555-3434 4 Thom Yorke 555-4545 5 Lenny Kravitz 555-5656 6 Mike Diamond 555-6767 6 rows in set (0.00 sec) ThisSELECTasks for*from the table namedmusicians. The*means “all fields” in the order that they are in the table. We can explicitly ask for the fields by listing them comma separated instead of using the star. mysql> SELECT player_id, name, phone FROM musicians;
6 rows in set (0.01 sec) The fields we select can be in any order. mysql> SELECT name, phone, player_id FROM musicians;
6 rows in set (0.00 sec) We can request specific fields—we don’t need to show all the fields available. mysql> SELECT name, phone FROM musicians; Please check back next week for the continuation of this article.
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