How many times did drivers travel more than 200 miles in a day? : COUNT « Aggregate Functions « SQL / MySQL






  1. SQL / MySQL
  2. Aggregate Functions
  3. COUNT

How many times did drivers travel more than 200 miles in a day?

        
mysql>
mysql>
mysql> CREATE TABLE driver_log
    -> (
    ->  rec_id          INT UNSIGNED NOT NULL AUTO_INCREMENT,
    ->  name            VARCHAR(20) NOT NULL,
    ->  trav_date       DATE NOT NULL,
    ->  miles           INT NOT NULL,
    ->  PRIMARY KEY (rec_id)
    -> );
Query OK, 0 rows affected (0.00 sec)

mysql>
mysql> INSERT INTO driver_log (name,trav_date,miles)
    ->  VALUES
    ->          ('Ben','2010-11-30',152),
    ->          ('Suzi','2010-11-29',391),
    ->          ('Henry','2010-11-29',300),
    ->          ('Henry','2010-11-27',96),
    ->          ('Ben','2010-11-29',131),
    ->          ('Henry','2010-11-26',115),
    ->          ('Suzi','2010-12-02',502),
    ->          ('Henry','2010-12-01',197),
    ->          ('Ben','2010-12-02',79),
    ->          ('Henry','2010-11-30',203)
    -> ;
Query OK, 10 rows affected (0.00 sec)
Records: 10  Duplicates: 0  Warnings: 0

mysql> SELECT COUNT(*) FROM driver_log WHERE miles > 200;
+----------+
| COUNT(*) |
+----------+
|        4 |
+----------+
1 row in set (0.00 sec)

mysql>
mysql> drop table driver_log;
Query OK, 0 rows affected (0.00 sec)

mysql>








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