arangodb/Documentation/Books/AQL/Operations

!CHAPTER High-level operations

The following high-level operations are described here after: 

* [FOR](For.md) : to iterate over all elements of an array.
* [RETURN](Return.md) : to produce the result of a query.
* [FILTER](Filter.md) : to restrict the results to elements that match an arbitrary logical condition. 
* [SORT](Sort.md) : to force a sort of the array of already produced intermediate results. 
* [LIMIT](Limit.md) : to reduce the number of elements in the result to at most the specified number.  
* [LET](Let.md) : to assign an arbitrary value to a variable.  
* [COLLECT](Collect.md) : to group an array by one or multiple group criteria. 
* [REMOVE](Remove.md) : to remove documents from a collection. 
* [UPDATE](Update.md) : to partially update documents in a collection. 
* [REPLACE](Replace.md) :  to completely replace documents in a collection. 
* [INSERT](Insert.md) : to insert new documents into a collection. 
* [UPSERT](Upsert.md) : to update an existing document, or create it in the case it does not exist.