---
name: "v.db.dropcolumn"
section: "1grass"
platform: "linux"
package: "grass-doc"
version: "8.4.1-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/v.db.dropcolumn"
---

# v.db.dropcolumn(1grass)

Drops a column from the attribute table connected to a given vector map.

## NAME

**v.db.dropcolumn**  - Drops a column from the attribute table connected to a given vector map.

## KEYWORDS

vector, attribute table, database

## SYNOPSIS

**v.db.dropcolumn**\
 **v.db.dropcolumn --help**\
 **v.db.dropcolumn** **map**=*name*  \[**layer**=*string*\]  **columns**=*name*\[,*name*,...\]  \[--**help**\]  \[--**verbose**\]  \[--**quiet**\]  \[--**ui**\]

### Flags:

- **--help**

  Print usage summary

- **--verbose**

  Verbose module output

- **--quiet**

  Quiet module output

- **--ui**

  Force launching GUI dialog

### Parameters:

- **map**=*name* **\[required\]**

  Name of vector map\
   Or data source for direct OGR access

- **layer**=*string*

  Layer number or name\
   Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.\
   Default: *1*

- **columns**=*name\[,name*,...\] **\[required\]**

  Name of attribute column(s) to drop

## DESCRIPTION

*v.db.dropcolumn* drops a column from the attribute table connected to a given vector map. It automatically checks the connection for the specified layer. *v.db.dropcolumn* omits to delete the ’cat’ column which is relevant to keep the connection between vector map and table.

## NOTES

*v.db.dropcolumn* is a front-end to *db.execute* to allow easier usage.

The existing database connection(s) can be verified with *v.db.connect*.

## EXAMPLES

Dropping a column:\
\

```
g.copy vect=roadsmajor,myroads
v.info -c myroads
v.db.dropcolumn myroads column=SHAPE_LEN
v.info -c myroads
```

## SEE ALSO

*db.connect,* *db.dropcolumn,* *db.execute,* *v.db.addcolumn,* *v.db.connect,* *v.db.droptable,* *v.db.select,* *v.db.update*

*GRASS SQL interface*

## AUTHOR

Markus Neteler

## SOURCE CODE

Available at: v.db.dropcolumn source code (history)

Accessed: Monday Feb 24 17:51:45 2025

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