Excerpt |
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Removes the specified column or columns permanently from your dataset. |
Tips:
- This transform might be automatically applied as one of the first steps of your recipe. See Initial Parsing Steps.
- If you want to hide a column from view, select Hide from the column drop-down. Note that the data can still be referenced in your transforms and appears in any generated output. See Transformer Page.
- If you are working with large datasets, you might want to drop columns at the beginning of your recipe, which can assist application and job execution performance. Use the tilde operator to drop ranges of columns.
- You can also specify the columns that you wish to retain and then add the
Keep
action to drop all other columns in the dataset.
Single-column example:
D code |
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drop col:ThisOldColumn action: Drop |
Output: Drops the column named ThisOldColumn
.
Multi-column example:
You can specify comma-separated sets of columns.
D code |
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drop col: FirstName, MiddleInitial action: Drop |
Output: Drops the columns FirstName
and MiddleInitial
from your dataset.
Keep example:
The following transform keeps the listed columns and drops all others in the dataset:
D code |
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drop col: FirstName, MiddleInitial action: Keep |
Output: Dataset only contains FirstName
and MiddleInitial
columns.
Column range example:
You can also specify ranges of columns using the tilde (~) operator:
D code |
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drop col:Column1~Column20 action: Drop |
Output: Drops the columns Column1
and Column20
and all columns displayed in between them in the data grid.
D code |
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drop col:column_ref action: [Drop|Keep] |
Token | Required? | Data Type | Description |
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drop | Y | transform | Name of the transform |
col | Y | string | Name of the column or expression for columns to drop |
action | Y | string | Drop or Keep the listed columns |
Identifies the column or columns to which to apply the transform. You can specify one column or more columns.
Include Page |
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| col_multi Parameter |
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| col_multi Parameter |
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|
Required? | Data Type |
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Yes | String (column name) |
Identifies whether the action performed by the transform:
Drop
- Listed columns are dropped from the dataset.Keep
- Listed columns are retained in the dataset, and all other columns are dropped.
Required? | Data Type |
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Yes | String (Drop or Keep ) |
See above.
D s also |
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label | wrangle_transform_drop |
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