Learning Mysql

+-------+-----------------------------------------------------+
| 1.34 | Intermission By Alan Wise Olympia, Paris 12/11/01] |
| 1.81 | In A Silent Way |
| 11.37 | Breaking Into Heaven |
| 12.80 | Human Nature |
| 16.67 | Shhh/Peaceful |
| 16.67 | In A Silent Way/It's About That Time |
| 2.38 | Rip This Joint |
| 2.78 | Jangling Jack |
| 2.81 | Full Nelson The results are ordered alphabetically, so that, for example, numbers beginning with appear before numbers beginning with 2. The CAST function forces a column to be treated as a different type, in this example as a character string using the AS CHAR
clause.
You can specify:
•
AS BINARY, to sort as binary, which has the same effect as ORDER BY BINARY
•
AS SIGNED, to sort as a signed integer
•
AS UNSIGNED, to sort as an unsigned integer
•
AS CHAR, to sort as a character string
•
AS DATE, to sort as a date
•
AS DATETIME
, to sort as a date and time
•
AS TIME, to sort as a time
The types of columns are discussed in detail in Column Types in Chapter 6.
The LIMIT Clause
The
LIMIT
clause is a useful, nonstandard SQL tool that allows you to control which rows are output. Its basic form allows you to limit the number of rows returned from a
SELECT
statement, which is useful when you want to limit the amount of data communicated over a network or output to the screen. You might use it, for example, in a web database application, where you want to find the rows that match a condition but only want to show the user the first 10 rows in a web page. Here’s an example:
mysql> SELECT track_name FROM track LIMIT 10;
+----------------------------+
| track_name |
+----------------------------+
| Do You Love Me |
| Nobody's Baby Now |
| Loverman |
| Jangling Jack |
| Red Right Hand |
| I Let Love In |
| Thirsty Dog |
| Ain't Gonna Rain Anymore |
| Lay Me Low |

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