Minor syntax changes.
I don't know Yii well enough, but I would suggest adding two additional examples: IS NOT NULL and LIKE 'foo%'

fixes #5331

Added support for arbitrary operators to Query::filterWhere, added support for arbitrary operators to Sphinx extension

fixes #3252

also improved unit tests for querybuilder buildLikeCondition

fix doc code according to yii2 core code style (When instantiating class it should be new MyClass(); instead of new MyClass;.)

Fixes #1586: `QueryBuilder::buildLikeCondition()` will now escape special characters and use percentage characters by default

this allows us to implement other activerecord implementations based on
NoSQL dbms