MongoDB "Joins" & $lookup (explained simply)

[@giorgiobrugnone6879]

Great video tnx.
Is it possible to query results by lookup field?
In your example is it possible to get all and only Posts with likes=5.0?
Thank you for reply

[@jurgenruegenberg2214]

To use the $lookup in the collections must they be already filled?, or how could it work when it's empty

[@TeddySmithDev]

When not full it’s shows []

[@amolmawale1443]

too good explained..