README

Installation

composer require francerz/sql-builder

Creating SELECT query

$query = Query::selectFrom(['g'=>'groups'],['group_id','subject','teacher']);

Compiles to:

SELECT g.group_id, g.subject, g.teacher FROM groups AS g

Adding WHERE clause

You can use the WHERE clause by retreiving the ConditionsList object returned by calling the where() method.

$query = Query::selectFrom(['g'=>'groups'],['group_id','subject','teacher']);
$query->where()->like('g.subject','%programming%');

Outputs:

SELECT g.group_id, g.subject, g.teacher FROM groups AS g WHERE g.subject LIKE '%programming%'

ConditionsList contains multiple methods each operator:

• Relative operators: equals(), notEquals(), lessThan(), lessEquals(), greaterThan(), greaterEquals().

  Also there are prefixed logic connectors (and, or) methods like: andLessThan(), orEquals().

• LIKE operator: like(), notLike(), andLike(), orLike(), andNotLike() and orNotLike().

• IS NULL operator: null(), notNull(), andNull(), orNull(), andNotNull() and orNotNull().

• BETWEEN operator: between(), notBetween(), andBetween(), orBetween(), andNotBetween() and orNotBetween().

• IN operator: in(), notIn(), andIn(), orIn(), andNotIn() and orNotIn().

Parentheses expressions

Conditions list allows using parentheses expresions by using a nested condition inside a callback.

To pass the callback you must use the __invoke(), not(), and(), or(), andNot() and orNot().

$query->where()(function($subwhere) {
    $subwhere
        ->between('g.group_id', 1, 100)
        ->orNull('g.teacher');
});

Output:

... WHERE (g.group_id BETWEEN 1 AND 100 OR g.teacher IS NULL)

#### Equals or NULL function

Theres also a method called equalsOrNull(), wich makes a perenthesis comparation between a value and another, or check if is null.

$query->where()->equalsOrNull('g.subject','Database Fundamentals');

Outputs:

... WHERE (g.subject = 'Database Fundamentals' OR g.subject IS NULL)

NOTE:
The ConditionsList object is also available with JOINS ON and HAVING clause.

Joining Tables

One of the most common action with databases is joining data from multiple tables. This package support most common joining operations. And each driver might translate these operations to compatible SQL Queries, meaning full support on any database engine.

Joining functions are: crossJoin(), innerJoin(), leftJoin(), rightJoin(), leftOuterJoin(), rightOuterJoin() and fullOuterJoin().

$query = Query::selectFrom(['g'=>'groups'], ['group_id']);
$query->innerJoin(['s'=>'subjects'], ['subject'=>'name'])
    ->on()->equals('s.subject_id', 'g.subject_id');
$query->leftJoin(['t'=>'teachers'], ['teacher'=>"CONCAT(first_name,' ',last_name)"])
    ->on()->equals('t.teacher_id', 'g.teacher_id');
$query->where()->in('g.group_id', [3, 5, 7, 11]);

Translates to:

SELECT g.group_id, s.name AS subject, CONCAT(first_name,' ',last_name) AS teacher
FROM groups AS g
INNER JOIN subjects AS s ON s.subject_id = g.subject_id
LEFT JOIN teachers AS t ON t.teacher_id = g.teacher_id
WHERE g.group_id IN (3, 5, 7, 11);

NOTE: Join Syntax is available to SELECT, UPDATE and DELETE sql syntax, however, not all database engines might support it.

SELECT nesting

Sometimes database table joining might not be enought for all the data requirements. Is quite often that for each row in a result of a query, another filtered result query must be executed.

This scenario produces excesive complex code to nest each result by each row. Also impacts performance by increasing the loops and database access roundtrips. For this reason there's a syntax that creates the most lightweight and efficient way to query nested data, preventing access overhead and reducing processing time.

// Students query
$studentsQuery = Query::selectFrom('students', ['student_id','first_name', 'last_name']);

// Groups query
$groupsQuery = Query::selectFrom('groups',['group_id','subject','teacher']);

// Nesting students by each group
$groupsQuery->nest(['Students'=>$studentsQuery], function(NestedSelect $nest, RowProxy $row) {
    $nest->getSelect()->where()->equals('s.group_id', $row->group_id);
});

Result might be like this:

[
    {
        "group_id": 1,
        "subject": "Programing fundamentals",
        "teacher": "Rosemary",
        "Students": [
            {
                "student_id": 325,
                "first_name": "Charlie",
                "last_name": "Ortega"
            },
            {
                "student_id": 743,
                "first_name": "Beth",
                "last_name": "Wilson"
            }
        ]
    },
    {
        "group_id": 2,
        "subject" : "Object Oriented Programming",
        "teacher": "Steve",
        "Students": [
            {
                "student_id": 536,
                "first_name": "Dylan",
                "last_name": "Morrison"
            }
        ]
    }
]