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https://github.com/gabfl/mysql_generate_series

mysql_generate_series is a MySQL replica of PostgreSQL's generate_series functions
https://github.com/gabfl/mysql_generate_series
mysql
Last synced: 18 days ago
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mysql_generate_series is a MySQL replica of PostgreSQL's generate_series functions
Host: GitHub
URL: https://github.com/gabfl/mysql_generate_series
Owner: gabfl
License: mit
Created: 2015-04-09T00:42:53.000Z (over 9 years ago)
Default Branch: main
Last Pushed: 2021-01-16T00:20:40.000Z (almost 4 years ago)
Last Synced: 2024-10-14T01:27:02.282Z (about 1 month ago)
Topics: mysql
Size: 14.6 KB
Stars: 61
Watchers: 5
Forks: 19
Open Issues: 0
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project

README

        # mysql_generate_series: generate_series for MySQL

mysql_generate_series is a MySQL version of PostgreSQL's [generate_series](http://www.postgresql.org/docs/current/static/functions-srf.html) functions.

This version is (heavily) adapted from the original and seeks to simplify the method call and make the MySQL version parameters follow the PostgreSQL version insofar as that is possible. 

It offers a single method `generate_series(start, stop, step)` to deliver a series from `start` to `stop` incrementing by `step`.

Calling the method generates no output but instead creates a temporary table called `series_tmp` in the current database which can be used in joins and sub-queries in the current session.

 

All parameters are `INTEGER` or strings which are representative of `INTEGER`, `DATE`, `DATETIME` and `INTERVAL` depending on the type of series being generated

## Installation

Install the methods from [sql/generate_series.sql](sql/generate_series.sql).

## INTEGER Series

For integer ranges the three parameters are all INTEGER or string representations of numbers.

### Usage

```sql

CALL generate_series(1, 20, 1);

```

Will create and populate `series_tmp` with INTEGER values from 1 to 20, incrementing by 1.

### Example

```sql

mysql> CALL generate_series( 1 , 10 , 1);

Query OK, 0 rows affected (0.05 sec)

mysql> DESC series_tmp;

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

| Field  | Type       | Null | Key | Default | Extra |

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

| series | bigint(20) | NO   | PRI | NULL    |       |

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

1 row in set (0.00 sec)

mysql> SELECT * FROM `series_tmp`;

+--------+

| series |

+--------+

|      1 |

|      2 |

|      3 |

|      4 |

|      5 |

|      6 |

|      7 |

|      8 |

|      9 |

|     10 |

+--------+

10 rows in set (0.00 sec)

```

## DATE Series

For date ranges the `start` and `stop` parameters are string representations of dates and `step` represents the `INTERVAL`.

### Usage

```sql

CALL generate_series('2018-01-01','2018-12-31','INTERVAL 1 DAY');

```

### Example

```sql

mysql> CALL generate_series('2018-01-01','2018-12-31','INTERVAL 1 MONTH');

Query OK, 0 rows affected (0.08 sec)

mysql> DESC series_tmp;

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

| Field  | Type | Null | Key | Default | Extra |

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

| series | date | NO   | PRI | NULL    |       |

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

1 row in set (0.00 sec)

mysql> SELECT * FROM `series_tmp`;

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

| series     |

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

| 2018-01-01 |

| 2018-02-01 |

| 2018-03-01 |

| 2018-04-01 |

| 2018-05-01 |

| 2018-06-01 |

| 2018-07-01 |

| 2018-08-01 |

| 2018-09-01 |

| 2018-10-01 |

| 2018-11-01 |

| 2018-12-01 |

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

12 rows in set (0.00 sec)

```

## DATETIME Series

For datetime ranges the `start` and `stop` parameters are datetimes and `step` represents the `INTERVAL`.

### Usage

```sql

CALL generate_series('2018-01-01 00:00:00', '2018-01-01 23:59:59', 'INTERVAL 1 SECOND');

```

### Example

```sql

mysql> CALL generate_series('2018-01-01 00:00:00', '2018-01-01 23:59:00', 'INTERVAL 1 MINUTE');

Query OK, 0 rows affected (0.07 sec)

mysql> DESC series_tmp;

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

| Field  | Type     | Null | Key | Default | Extra |

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

| series | datetime | NO   | PRI | NULL    |       |

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

1 row in set (0.01 sec)

mysql> SELECT * FROM `series_tmp`;

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

| series              |

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

| 2018-01-01 00:00:00 |

| 2018-01-01 00:01:00 |

| 2018-01-01 00:02:00 |

| 2018-01-01 00:03:00 |

| 2018-01-01 00:04:00 |

| 2018-01-01 00:05:00 |

| 2018-01-01 00:06:00 |

| 2018-01-01 00:07:00 |

| 2018-01-01 00:08:00 |

...

| 2018-01-01 23:56:00 |

| 2018-01-01 23:57:00 |

| 2018-01-01 23:58:00 |

| 2018-01-01 23:59:00 |

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

1440 rows in set (0.00 sec)

```

## INTERVALS

The following INTERVAL types are supported:

 - `SECOND`

 - `MINUTE`

 - `HOUR`

 - `DAY`

 - `WEEK`

 - `MONTH`

 - `YEAR`

## Other examples

### Inserting in a table from a series

MySQL does not support functions returning tables so the procedure must be run before the data can be used from `series_tmp`.

The following example shows how to insert multiple rows in MySQL tables easily:

```sql

-- Create a test table

mysql> CREATE TABLE test (a int, b text);

Query OK, 0 rows affected (0.01 sec)

-- Generate a series from 1 to 10

mysql> CALL generate_series(1, 10, 1);

Query OK, 0 rows affected (0.00 sec)

-- Insert all the rows from the series into the test table

mysql> INSERT INTO test (a, b) SELECT series, 'This is a test' FROM `series_tmp`;

Query OK, 10 rows affected (0.00 sec)

Records: 10  Duplicates: 0  Warnings: 0

-- Display the test table content

mysql> SELECT * FROM test;

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

| a    | b              |

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

|    1 | This is a test |

|    2 | This is a test |

|    3 | This is a test |

|    4 | This is a test |

|    5 | This is a test |

|    6 | This is a test |

|    7 | This is a test |

|    8 | This is a test |

|    9 | This is a test |

|   10 | This is a test |

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

10 rows in set (0.00 sec)

```

### Querying in a table using a series

As for inserts, MySQL does not allow using a stored procedure directly in a SELECT query.

We can again use mysql_generate_series's temporary table `series_tmp` to use the series with a JOIN in a SELECT query

This example demonstrates how to display all hours from a date and their eventual associated row in another table:

```sql

-- Create test table

mysql> CREATE TABLE test2 (a datetime, b text);

Query OK, 0 rows affected (0.03 sec)

-- Insert 2 lines

mysql> INSERT INTO test2 (a, b) VALUES ('2015-09-03 02:00:00', 'Line 1'),

    ->                                 ('2015-09-03 14:00:00', 'Line 2');

Query OK, 2 rows affected (0.00 sec)

Records: 2  Duplicates: 0  Warnings: 0

-- Generate a series of each hour of the day

mysql> CALL generate_series('2015-09-03 00:00:00', '2015-09-03 23:00:00', 'INTERVAL 1 HOUR');

Query OK, 0 rows affected (0.00 sec)

-- Select "test2" content

mysql> SELECT * FROM test2;

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

| a                   | b      |

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

| 2015-09-03 02:00:00 | Line 1 |

| 2015-09-03 14:00:00 | Line 2 |

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

2 rows in set (0.00 sec)

-- Select "test2" content with all hours of the day

mysql> SELECT series_tmp.series, test2.a, test2.b

    -> FROM series_tmp

    -> LEFT JOIN test2 ON series_tmp.series = test2.a

    -> ORDER BY series_tmp.series;

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

| series              | a                   | b      |

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

| 2015-09-03 00:00:00 | NULL                | NULL   |

| 2015-09-03 01:00:00 | NULL                | NULL   |

| 2015-09-03 02:00:00 | 2015-09-03 02:00:00 | Line 1 |

| 2015-09-03 03:00:00 | NULL                | NULL   |

| 2015-09-03 04:00:00 | NULL                | NULL   |

| 2015-09-03 05:00:00 | NULL                | NULL   |

| 2015-09-03 06:00:00 | NULL                | NULL   |

| 2015-09-03 07:00:00 | NULL                | NULL   |

| 2015-09-03 08:00:00 | NULL                | NULL   |

| 2015-09-03 09:00:00 | NULL                | NULL   |

| 2015-09-03 10:00:00 | NULL                | NULL   |

| 2015-09-03 11:00:00 | NULL                | NULL   |

| 2015-09-03 12:00:00 | NULL                | NULL   |

| 2015-09-03 13:00:00 | NULL                | NULL   |

| 2015-09-03 14:00:00 | 2015-09-03 14:00:00 | Line 2 |

| 2015-09-03 15:00:00 | NULL                | NULL   |

| 2015-09-03 16:00:00 | NULL                | NULL   |

| 2015-09-03 17:00:00 | NULL                | NULL   |

| 2015-09-03 18:00:00 | NULL                | NULL   |

| 2015-09-03 19:00:00 | NULL                | NULL   |

| 2015-09-03 20:00:00 | NULL                | NULL   |

| 2015-09-03 21:00:00 | NULL                | NULL   |

| 2015-09-03 22:00:00 | NULL                | NULL   |

| 2015-09-03 23:00:00 | NULL                | NULL   |

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

24 rows in set (0.00 sec)

```

## Tips and tricks

The temporary table used to store results `series_tmp` is dropped and recreated on each call to generate_series(). As a temporary table, `series_tmp` will only be available within the current session and to the current user. It will also automatically dropped when the connection is closed.

## Authors

**Gabriel Bordeaux**

+ [Website](http://www.gab.lc/) 

+ [Twitter](https://twitter.com/gabrielbordeaux)

**Paul Campbell**

+ [Website](http://www.animalcarpet.com/)