php-mysql/README.md
vlw 619f43b3bf fix(doc): remove reference to removed method flatten() from README (#38)
Closes #14

Reviewed-on: https://codeberg.org/vlw/php-mysql/pulls/38
Co-authored-by: vlw <victor@vlw.se>
Co-committed-by: vlw <victor@vlw.se>
2024-09-25 13:28:15 +00:00

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8.1 KiB
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# php-mysql
This is a simple abstraction library for MySQL DML operations.
For example:
```php
MySQL->for(string $table)
->where(?array ...$conditions)
->order(?array $order_by)
->limit(int|array|null $limit)
->select(array $columns): array|bool;
```
which would be equivalent to the following in MySQL:
```sql
SELECT $columns FROM $table WHERE $filter ORDER BY $order_by LIMIT $limit;
```
> [!IMPORTANT]
> This library requires the [`MySQL Improved`](https://www.php.net/manual/en/book.mysqli.php) extension and requires PHP 8.0 or newer.
## Install from composer
```
composer require vlw/mysql
```
```php
use vlw\MySQL\MySQL;
```
# Example / Documentation
Available statements
Statement|Method
--|--
`SELECT`|[`select()`](#select)
`UPDATE`|[`update()`](#update)
`INSERT`|[`insert()`](#insert)
`DELETE`|[`delete()`](#delete)
`WHERE`|[`where()`](#where)
`ORDER BY`|[`order()`](#order-by)
`LIMIT`|[`limit()`](#limit)
----
`Example table name: beverages`
id|beverage_type|beverage_name|beverage_size
--|--|--|--
0|coffee|cappuccino|10
1|coffee|black|15
2|tea|green|10
3|tea|black|15
```php
use vlw\MySQL\MySQL;
// Pass through: https://www.php.net/manual/en/mysqli.construct.php
$db = new MySQL($host, $user, $pass, $db);
```
All executor methods [`select()`](#select), [`update()`](#update), and [`insert()`](#insert) will return a [`mysqli_result`](https://www.php.net/manual/en/class.mysqli-result.php) object or boolean.
# FOR
```php
MySQL->for(
string $table
): self;
```
All queries start by chaining the `for(string $table)` method. This will define which database table the current query should be executed on.
*Example:*
```php
MySQL->for("beverages")->select("beverage_type");
```
# SELECT
Chain `MySQL->select()` anywhere after a [`MySQL->for()`](#for) to retrieve columns from a database table.
Pass an associative array of strings, CSV string, or null to this method to filter columns.
```php
MySQL->select(
array|string|null $columns
): mysqli_result|bool;
```
In most cases you probably want to select with a constraint. Chain the [`where()`](#where) method before `select()` to filter the query
### Example
```php
$beverages = MySQL->for("beverages")->select(["beverage_name", "beverage_size"]); // SELECT beverage_name, beverage_size FROM beverages
```
```
[
[
"beverage_name" => "cappuccino",
"beverage_size" => 10
],
[
"beverage_name" => "black",
"beverage_size" => 15
],
// ...etc
]
```
# INSERT
Chain `MySQL->insert()` anywhere after a [`MySQL->for()`](#for) to append a new row to a database table.
Passing a sequential array to `insert()` will assume that you wish to insert data for all defined columns in the table. Pass an associative array of `[column_name => value]` to INSERT data for specific columns (assuming the other columns have a [DEFAULT](https://dev.mysql.com/doc/refman/8.0/en/data-type-defaults.html) value defined).
```php
MySQL->insert(
// Array of values to INSERT
array $values
): mysqli_result|bool
// Returns true if row was inserted
```
#### Example
```php
MySQL->for("beverages")->insert([
null,
"coffee",
"latte",
10
]);
// INSERT INTO beverages VALUES (null, "coffee", "latte", 10);
```
```
true
```
# DELETE
Chain `MySQL->delete()` anywhere after a [`MySQL->for()`](#for) to remove a row or rows from the a database table.
```php
MySQL->delete(
array ...$conditions
): mysqli_result|bool
// Returns true if at least one row was deleted
```
This method takes at least one [`MySQL->where()`](#where)-syntaxed argument to determine which row or rows to delete. Refer to the [`MySQL->where()`](#where) section for more information.
#### Example
```php
MySQL->for("beverages")->insert([
null,
"coffee",
"latte",
10
]);
// INSERT INTO beverages VALUES (null, "coffee", "latte", 10);
```
```
true
```
# UPDATE
Chain `MySQL->update()` anywhere after a [`MySQL->for()`](#for) to modify existing rows in a database table.
```php
MySQL->update(
// Key, value array of column names and values to update
array $fields,
): mysqli_result|bool;
// Returns true if at least 1 row was changed
```
### Example
```php
MySQL->for("beverages")->update(["beverage_size" => 10]); // UPDATE beverages SET beverage_size = 10
```
```php
true
```
In most cases you probably want to UPDATE against a constaint. Chain a [`where()`](#where) method before [`MySQL->update()`](#update) to set constraints
# WHERE
Filter a [`MySQL->select()`](#select) or [`MySQL->update()`](#update) method by chaining the `MySQL->where()` method anywhere before it. The [`MySQL->delete()`](#delete) executor method also uses the same syntax for its arguments.
Each key, value pair will be `AND` constrained against each other.
```php
MySQL->where(
?array ...$conditions
): self;
```
### Example
```php
$coffee = MySQL->for("beverages")->where(["beverage_type" => "coffee"])->select(["beverage_name", "beverage_size"]); // SELECT beverage_name, beverage_size FROM beverages WHERE (beverage_type = "coffee");
```
```php
[
[
"beverage_name" => "cappuccino",
"beverage_size" => 10
],
[
"beverage_name" => "black",
"beverage_size" => 15
]
]
```
## Capture groups
### AND
Add additional key value pairs to an array passed to `where()` and they will all be compared as AND with each other.
```php
MySQL->where([
"beverage_type" => "coffee",
"beverage_size" => 15
]);
```
```sql
WHERE (beverage_type = 'coffee' AND beverage_size = 15)
```
### OR
Passing an additional array of key values as an argument will OR it with all other arrays passed.
```php
$filter1 = [
"beverage_type" => "coffee",
"beverage_size" => 15
];
$filter2 = [
"beverage_type" => "tea",
"beverage_name" => "black"
];
MySQL->where($filter1, $filter2, ...);
```
```sql
WHERE (beverage_type = 'coffee' AND beverage_size = 15) OR (beverage_type = 'tea' AND beverage_name = 'black')
```
## Define custom operators
By default, all values in an the assoc array passed to `where()` will be treated as an `EQUALS` (=) operator.
```php
MySQL->where(["column" => "euqals_this_value"]);
```
Setting the value of any key to another assoc array will allow for more "advanced" filtering by defining your own [`Operators`](https://github.com/VictorWesterlund/php-libmysqldriver/blob/master/src/Operators.php).
The key of this subarray can be any MySQL operator string, or the **->value** of any case in the [`Operators`](https://github.com/VictorWesterlund/php-libmysqldriver/blob/master/src/Operators.php) enum.
```php
MySQL->where([
"beverage_name" => [
Operators::LIKE->value => "%wildcard_contains%"
]
]);
```
# ORDER BY
Chain the `MySQL->order()` method before a [`MySQL->select()`](#select) statement to order by a specific column
```php
MySQL->order(
?array $order_by
): self;
```
```php
$coffee = MySQL->for("beverages")->order(["beverage_name" => "ASC"])->select(["beverage_name", "beverage_size"]); // SELECT beverage_name, beverage_size FROM beverages ORDER BY beverage_name ASC
```
```php
[
[
"beverage_name" => "tea",
"beverage_size" => 10
],
[
"beverage_name" => "tea",
"beverage_size" => 15
],
// ...etc for "beverage_name = coffee"
]
```
# LIMIT
Chain the `limit()` method before a [`MySQL->select()`](#select) statement to limit the amount of columns returned
```php
MySQL->limit(
?int $limit,
?int $offset = null
): self;
```
## Passing a single integer argument
This will simply `LIMIT` the results returned to the integer passed
```php
$coffee = MySQL->for("beverages")->limit(1)->select(["beverage_name", "beverage_size"]); // SELECT beverage_name, beverage_size FROM beverages WHERE beverage_type = "coffee" LIMIT 1
```
```php
[
[
"beverage_name" => "cappuccino",
"beverage_size" => 10
]
]
```
## Passing two integer arguments
This will `OFFSET` and `LIMIT` the results returned. The first argument will be the `LIMIT` and the second argument will be its `OFFSET`.
```php
$coffee = MySQL->for("beverages")->limit(3, 2)->select(["beverage_name", "beverage_size"]); // SELECT beverage_name, beverage_size FROM beverages LIMIT 3 OFFSET 2
```
```php
[
[
"beverage_name" => "tea",
"beverage_size" => 10
],
[
"beverage_name" => "tea",
"beverage_size" => 15
],
// ...etc
]
```