Now that you have gone through the basics of the different core SQL statements, it is time to really work with the
SELECT
statement.
SELECT is extremely powerful, and can provide some amazing sets of information once you understand how best to use it. The main strength of the
SELECT
statement comes from your ability to define what information you need. What this means is that you have the ability to "cut" the database tables any number of ways.With
SELECT,
you can limit which columns are returned, which and how many rows are returned.
In this module, you will learn more about the
SELECT
statement, how to use it, and how to leverage the different filtering capabilities to your advantage. You will see how to create a results set that exactly matches what you are looking for.
You can filter and control the results from your SQL statements by using two techniques. We'll cover these in the next two lessons.
The SELECT INTO statement copies data from one table and inserts it into a new table.
+---------------------------+-------------------------------------+
| artist_name | album_name |
+---------------------------+-------------------------------------+
| New Order | Retro - John McCready FAN |
| New Order | Substance (Disc 2) |
| New Order | Retro - Miranda Sawyer POP |
| New Order | Retro - New Order / Bobby Gillespie LIVE |
| New Order | Power, Corruption & Lies |
| New Order | Substance 1987 (Disc 1) |
| New Order | Brotherhood |
| Nick Cave & The Bad Seeds | Let Love In |
| Miles Davis | Live Around The World |
| Miles Davis | In A Silent Way |
| The Rolling Stones | Exile On Main Street |
| The Stone Roses | Second Coming |
| Kylie Minogue | Light Years |
+---------------------------+-------------------------------------+
13 rows in set (0.10 sec)
We can change this SELECT query slightly to write this data into an output file as commaseparated values:
mysql>
SELECT artist_name, album_name
FROM artist, album
WHERE artist.artist_id=album.artist_id
INTO OUTFILE '/tmp/artists_and_albums.csv' FIELDS TERMINATED BY ',';
Query OK, 13 rows affected (0.02 sec)
Here, we have saved the results into the file artists_and_albums.csv in the /tmp directory;
the MySQL server must be able to write to the directory that you specify. On a Windows system, specify a path such as C:\artists_and_albums.csv instead. If you omit the FIELDS