> For the complete documentation index, see [llms.txt](https://docs.rasgoml.com/rasgo-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.rasgoml.com/rasgo-docs/rasgo-0.1/all-transforms/vlookup.md).

# Vlookup

## Inspired by Excel... a VLookup experience that works in SQL

### Required Inputs

* Lookup Column: The column to look up in the Lookup Table. Make sure the column is named the same in both tables.
* Lookup Table: The table to look up the Lookup Column in.

### Optional Inputs

* Keep Columns: The columns to keep from the Lookup Table. If not provided, all columns from the Lookup Table will be kept.

### Notes

* For values that don't find a match in the lookup\_column, you will see Null
* For columns that have the same name in both tables, the columns in the Lookup Table will be prefixed with the table name

## Parameters

| Name           | Type         | Description                            | Is Optional |
| -------------- | ------------ | -------------------------------------- | ----------- |
| lookup\_column | column       | Column to look up in the lookup table  |             |
| lookup\_table  | table        | Table to look up the lookup\_column in |             |
| keep\_columns  | column\_list | Columns to keep from the lookup table  | True        |

## Example

```python
internet_sales = rasgo.get.dataset(74)
customer = rasgo.get.dataset(55)
product = rasgo.get.dataset(75)

ds2 = internet_sales.vlookup(
  lookup_column='PRODUCTKEY',
  lookup_table=product.fqtn,
  keep_columns=['WEIGHT', 'ENGLISHDESCRIPTION']
)
ds2.preview()
```

## Source Code

{% embed url="<https://github.com/rasgointelligence/RasgoTransforms/blob/main/rasgotransforms/rasgotransforms/transforms/vlookup/vlookup.sql>" %}


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