fixes #5601

Fixes #4938: When `yii\db\ActiveQuery` is used to build sub-queries, its WHERE clause is not correctly generated

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

one method for fetching data and one for sending to db.

fixes #2287

issue #3494

Revert "Fixes #3469: Fixed the bug that `QueryBuilder::getColumnType()` may drop the provided column precision in certain cases"

This reverts commit a46efe79.

This reverts commit 70b57766.

Fixes #3469: Fixed the bug that `QueryBuilder::getColumnType()` may drop the provided column precision in certain cases

fixes #3252

also improved unit tests for querybuilder buildLikeCondition

issue #2852

Fixes #2571: Fixed the bug that batchInsert will fail for SQLite if the values contain null or boolean false;
Fixes #2683: Fixed the bug that batchInsert will fail for MySQL if the values contain boolean false.