MySQL BETWEEN Clause

You can use BETWEEN clause to replace a combination of "greater than equal AND less than equal" conditions. To understand BETWEEN clause, consider an employee_tbl table, which is having the following records:

mysql > SELECT * FROM employee_tbl ; +------+------+------------+--------------------+ | id

1 | John | 2007 - 01 - 24 |

2 | Ram | 2007 - 05 - 27 |

3 | Jack | 2007 - 05 - 06 |

3 | Jack | 2007 - 04 - 06 |

4 | Jill | 2007 - 04 - 06 |

5 | Zara | 2007 - 06 - 06 |

5 | Zara | 2007 - 02 - 06 |

+------+------+------------+--------------------+

7 rows in set ( 0.00 sec )

Now, suppose based on the above table you want to fetch records with conditions daily_typing_pages more than 170 and equal and less than 300 and equal. This can be done using >= and <= conditions as follows:

mysql > SELECT * FROM employee_tbl

-> WHERE daily_typing_pages >= 170 AND -> daily_typing_pages <= 300 ;

+------+------+------------+--------------------+ | id

| name | work_date | daily_typing_pages | +------+------+------------+--------------------+

1 | John | 2007 - 01 - 24 |

2 | Ram | 2007 - 05 - 27 |

3 | Jack | 2007 - 05 - 06 |

4 | Jill | 2007 - 04 - 06 |

5 | Zara | 2007 - 06 - 06 |

+------+------+------------+--------------------+

5 rows in set ( 0.03 sec )

Same can be achieved using BETWEEN clause as follows: mysql > SELECT * FROM employee_tbl

-> WHERE daily_typing_pages BETWEEN 170 AND 300 ; +------+------+------------+--------------------+ | id

1 | John | 2007 - 01 - 24 |

2 | Ram | 2007 - 05 - 27 |

3 | Jack | 2007 - 05 - 06 |

4 | Jill | 2007 - 04 - 06 |

5 | Zara | 2007 - 06 - 06 |

+------+------+------------+--------------------+

5 rows in set ( 0.03 sec )

MySQL UNION Keyword

You can use UNION if you want to select rows one after the other from several tables or several sets of rows from

a single table all as a single result set. UNION is available as of MySQL 4.0. This section illustrates how to use it.

Suppose you have two tables that list prospective and actual customers, a third that lists vendors from whom you purchase supplies, and you want to create a single mailing list by merging names and addresses from all three tables. UNION provides a way to do this. Assume the three tables have the following contents:

mysql > SELECT * FROM prospect ; +---------+-------+------------------------+ | fname | lname | addr

+---------+-------+------------------------+

| Peter | Jones | 482 Rush St ., Apt . 402 |

| Bernice | Smith | 916 Maple Dr .

+---------+-------+------------------------+ mysql > SELECT * FROM customer ; +-----------+------------+---------------------+ | last_name | first_name | address

+-----------+------------+---------------------+ | Peterson | Grace

| 16055 Seminole Ave . |

| Smith | Bernice

| 916 Maple Dr .

| Brown | Walter

| 8602 1st St .

+-----------+------------+---------------------+ mysql > SELECT * FROM vendor ; +-------------------+---------------------+ | company

| street

+-------------------+---------------------+

+-------------------+---------------------+

It does not matter if all the three tables have different column names. The following query illustrates how to select names and addresses from the three tables all at once:

mysql > SELECT fname , lname , addr FROM prospect -> UNION -> SELECT first_name , last_name , address FROM customer -> UNION

-> SELECT company , '' , street FROM vendor ;

+-------------------+----------+------------------------+ | fname

| lname

| addr

+-------------------+----------+------------------------+ | Peter

| Jones

| 482 Rush St ., Apt . 402 |

| Bernice

| Smith

| 916 Maple Dr .

| Grace

| Peterson | 16055 Seminole Ave .

| Walter

| Brown

| 8602 1st St .

| ReddyParts , Inc . |

| 38 Industrial Blvd .

| Parts - to - go , Ltd . |

| 213B Commerce Park .

+-------------------+----------+------------------------+ If you want to select all records, including duplicates, follow the first UNION keyword with ALL: mysql > SELECT fname , lname , addr FROM prospect

-> UNION ALL -> SELECT first_name , last_name , address FROM customer -> UNION

-> SELECT company , '' , street FROM vendor ;

+-------------------+----------+------------------------+ | fname

| lname

| addr

+-------------------+----------+------------------------+ | Peter

| Jones

| 482 Rush St ., Apt . 402 |

| Bernice

| Smith

| 916 Maple Dr .

| Grace

| Peterson | 16055 Seminole Ave .

| Bernice

| Smith

| 916 Maple Dr .

| Walter

| Brown

| 8602 1st St .

| ReddyParts , Inc . |

| 38 Industrial Blvd .

| Parts - to - go , Ltd . |

| 213B Commerce Park .

+-------------------+----------+------------------------+

MySQL BETWEEN Clause