> For the complete documentation index, see [llms.txt](https://help.novacuraflow.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.novacuraflow.com/development/flowscript/table/x-eval.md).

# Eval

This Flow Script tutorial explains how to use the Eval function with syntax and examples.

### D**escription**‌

> It is recommended to always use Eval for table operations in large datasets for better performance.

The Eval function in [FlowScript ](/development/flowscript.md)is used to force the evaluation of a [table](/development/flowscript/table.md) expression.\
\
We recommend always using Eval() when dealing with large datasets. It is particularly useful when you need to pre-process or filter data in a table and plan to reuse this processed data later in your script. \
\
Eval essentially pre-calculates and stores the results of your table query, making your script more efficient by preventing the need to recompute the same data. 

### **Syntax**

‌The syntax for the Eval function is:

`Eval(table where x < 0)`

#### ‌**Parameters**

table - the table on which the query is to be performed.

### **Returns**

‌The Eval function returns a new table.


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