php-mysql/README.md
Victor Westerlund eed7a470ed
feat: remove table model by passing null to with() (#19)
* feat: remove table model by passing null to with()

* feat(doc): add with() in README
2023-11-02 11:53:54 +01:00

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# php-libmysqldriver
This library provides abstraction methods for common operations on MySQL-like databases like `SELECT`, `UPDATE`, and `INSERT` using method chaining for the various MySQL features.
For example:
```php
$db->for(string $table)
->with(array $model)
->where(array $filters)
->order(array $order_by)
->limit(1)
->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;
```
This library is built on top of the PHP [`MySQL Improved`](https://www.php.net/manual/en/book.mysqli.php) extension.
## Install from composer
```
composer require victorwesterlund/libmysqldriver
```
```php
use libmysqldriver/MySQL;
```
# Example / Documentation
Available statements
Statement|Method
--|--
`SELECT`|[`select()`](#select)
`UPDATE`|[`update()`](#update)
`INSERT`|[`insert()`](#insert)
`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 libmysqldriver\MySQL;
// Pass through: https://www.php.net/manual/en/mysqli.construct.php
$db = new MySQL($host, $user, $pass, $db);
```
# SELECT
Use `MySQL->select()` to retrieve columns from a database table.
Pass an associative array of strings, CSV string, or null to this method to filter columns.
```php
$db->select(
array|string|null $columns
): array|bool;
// Returns array of arrays for each row, or bool if no columns were defined
```
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 = $db->for("beverages")->select(["beverage_name", "beverage_size"]); // SELECT beverage_name, beverage_size FROM beverages
$beverages = $db->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
]
```
## Flatten array to single dimension
If you don't want an array of arrays and would instead like to access each key value pair directly. Chain the `MySQL->flatten()` anywhere before `MySQL->select()`.
This will return the key value pairs of the first entry directly.
> **Note**
> This method will not set `LIMIT 1` for you. It is recommended to chain `MySQL->limit(1)` anywhere before `MySQL->select()`. [You can read more about it here](https://github.com/VictorWesterlund/php-libmysqldriver/issues/14)
```php
$coffee = $db->for("beverages")->limit(1)->flatten()->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
]
```
# INSERT
Use `MySQL->insert()` to append a new row to a database table
```php
$db->insert(
// Array of values to INSERT
array $values
): bool
// Returns true if row was inserted
```
#### Example
```php
$db->for("beverages")->insert([
null,
"coffee",
"latte",
10
]);
// INSERT INTO beverages VALUES (null, "coffee", "latte", 10);
```
```
true
```
# UPDATE
Modify existing rows with `MySQL->update()`
```php
$db->get(
// Key, value array of column names and values to update
array $fields,
): bool;
// Returns true if at least 1 row was changed
```
### Example
```php
$db->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 `update()` to set constraints
# WHERE
Filter a `select()` or `update()` method by chaining the `MySQL->where()` method anywhere before it.
### Example
```php
$coffee = $db->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
]
]
```
## Advanced filtering
You can do more detailed filtering by passing more constraints into the same array, or even futher by passing multiple arrays each with filters.
### 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')
```
# ORDER BY
Chain the `order()` method before a `select()` statement to order by a specific column
```php
$coffee = $db->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 `select()` statement to limit the amount of columns returned
> **Note**
> You can also flatten to a single dimensional array from the first entity by chaining [`MySQL->flatten()`](#flatten-array-to-single-dimension)
## Passing an integer to LIMIT
This will simply `LIMIT` the results returned to the integer passed
```php
$coffee = $db->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 an associative array to LIMIT
This will `OFFSET` and `LIMIT` the results returned from the first key of the array as `OFFSET` and the value of that key as `LIMIT`
```php
$coffee = $db->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
]
```
----
# Restrict affected/returned database columns to table model
Chain and pass an array to `MySQL->with()` before a `select()`, `update()`, or `insert()` method to limit which columns will be returned/affected. It will use the **values** of the array so it can be either sequential or associative.
**This method will cause `select()`, `update()`, and `insert()` to ignore any columns that are not present in the passed table model.**
You can remove an already set table model by passing `null` to `MySQL->with()`