.drop column command
Applies to: ✅ Microsoft Fabric ✅ Azure Data Explorer
Removes a column from a table.
To drop multiple columns from a table, see drop multiple table columns.
Note
This command does not physically delete the data, and does not reduce the cost of storage for data that was already ingested.
Warning
This command is irreversible. All data in the column that is removed will no longer by queryable. Future commands to add that column back will not be able to restore the data.
Permissions
You must have at least Table Admin permissions to run this command.
Syntax
.drop column TableName.ColumnName [ifexists]
Learn more about syntax conventions.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
| TableName | string |
✔️ | The name of the table containing the column to drop. |
| ColumnName | string |
✔️ | The name of the column to drop. |
ifexists |
string |
If specified, the command won't fail on a non-existent column. |
Example
The following command will drop the Value column from the Test table, if such a column exists. If the column doesn't exist, the command will not fail.
.drop column Test.Value ifexists
Drop multiple table columns
Removes multiple columns from a table.
Note
This command does not physically delete the data, and does not reduce the cost of storage for data that was already ingested.
Warning
This command is irreversible. All data in the column that is removed will no longer by queryable. Future commands to add those columns back will not be able to restore the data.
Syntax
.drop table TableName columns ( ColumnName [, ...] )
Learn more about syntax conventions.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
| TableName | string |
✔️ | The name of the table containing the column to drop. |
| ColumnName | string |
✔️ | The name of the column to drop. |
Example
The following command will drop the Value and Item columns from the Test table.
.drop table Test columns ( Value, Item )