Documentation extended, added some exceptions

• Documentation extended
• Added some exceptions
• DBOrderSpec: If a statement contains an alias that was not defined before, then an exception is thrown now

Fixed DBExprFilter and Limit and Offset can now be optional

• Fixed DBExprFilter: validator and validationResultHandler are only taken into account if key exists
• Limit and Offset can now take a parameter of Type OptionalValue, which can make both optional

Documentation extended, added some exceptions

• Documentation extended
• Added some exceptions
• DBOrderSpec: If a statement contains an alias that was not defined before, then an exception is thrown now

Release for wrong commit

• Wront commit. Ignore this one.

Fixed type-hints

• Fixed type hint of Kir\MySQL\Builder\Update::set(..., $value)
• Fixed type hint of Kir\MySQL\Builder\Traits\WhereBuilder::where and clarify that $expression could be an object

Project now requires min PHP7.1 and is PHP 8.0 compatible

• Updated php-version constraint from 7.0 to 7.1
• Fixed compatibility issues with php 8.0
• Upgraded phpunit base version to 6.0
• Fixed Declaration of Kir\MySQL\Common\DBTestCase::setUp() must be compatible with PHPUnit\Framework\TestCase::setUp(): void

Various bug-fixes

• Select-Statements: WHERE and HAVING clauses can now be called alternatively to arrays with an object as expression parameter.
• Select-Statements: WHERE and HAVING clauses can now be called with an empty array or an empty object. As a result, no HAVING or WHERE is generated. Previously, an empty WHERE or HAVING was output.
• Various minor changes

Min PHP-version raised to 7.0

• Raised PHP min version to 7.0
• Various minor changes
• Added composer run-script phpstan and composer run-script phpunit

Disabled phpstan for travis temporarly

0.1.54.1

- Disabled phpstan for travis temporarly

x=NULL-Values are now projected as ISNULL(x) in some cases

NULL-Values used in conjunction with Select::where and Select::having when conditions are used as a key-value-array are now projected with ISNULL instead of field=NULL.

$str = $select
->field('a')
->from('t', 'test')
->where(['field' => null])
->asString();

will result in

SELECT
    a
FROM
    test t
WHERE
    (ISNULL(`field`))