| Excerpt |
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Creates an Object or Array of values using column names and their values as key-value pairs for one or more columns. Generated column type is determined by the into parameter. |
The nest transform is the opposite of unnest, which unpacks Object data into separate columns and rows. See Unnest Transform.
Object example:
| D code |
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nest col:ItemA,ItemB into:'obj' as:'myObj' |
Output: See below.
| ItemA | ItemB | myObj |
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| 22 | 33 | {"ItemA":"22","ItemB","33"} |
| 44 | 55 | {"ItemA":"44","ItemB","55"} |
Array example:
| D code |
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nest col:ItemA,ItemB into:'array' as:'myArray' |
Output: Output arrays do not include the column name.
| ItemA | ItemB | myArray |
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| 22 | 33 | ["22","33"] |
| 44 | 55 | ["44","55"] |
| D code |
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nest col:column_ref [into: object|array] [as:'new_column_name'] |
| Token | Required? | Data Type | Description |
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| nest | Y | transform | Name of the transform |
| col | Y | string | Source column name |
| into | N | string | Data type of output column: object (default) or array |
| as | N | string | Name of newly generated column |
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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For each listed column, a new pair of key and value columns is generated.
| D code |
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nest col: Qty, Amount |
Output: Builds an Object of the data from the columns Qty and Amount .
You can also specify ranges of columns using the tilde (~) operator:
| D code |
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nest col:Column1~Column20 as:'bigNest' |
Output: Nests the data from columns Column1 and Column20 and all columns displayed in between them in the data grid into the new column bigNest.
| Required? | Data Type |
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| Yes | String (column name) |
Defines the output column type. Accepted values:
If this parameter is not specified, the output type is Object.
| Required? | Data Type |
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| No (Object is default) | String (data type name) |
| D code |
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nest col: CustId,ProdId as:'masterNest' |
Output: Nests the data from the columns CustId and ProdId into a new column called, masterNest.
| Required? | Data Type |
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| No | String (column name) |
Source:
In the following example, furniture product dimensions are stored in separate columns in cm.
| ProductCategory | ProductName | Length_cm | Width_cm | Height_cm |
|---|
| bench | Hooska | 118.11 | 74.93 | 46.34 |
| lamp | Tansk | 30.48 | 30.48 | 165.1 |
| bookshelf | Brock | 27.94 | 160.02 | 201.93 |
| couch | Loafy | 95 | 227 | 83 |
Transform:
Use the nest transform to bundle the data into a single column.
| D code |
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nest col:Length~Height as:'ProductDimensions_cm' |
Results:
In the following example, furniture product dimensions are stored in separate columns in cm.
| ProductCategory | ProductName | Length_cm | Width_cm | Height_cm | ProductDimensions_cm |
|---|
| bench | Hooska | 118.11 | 74.93 | 46.34 | {"Length_cm":"118.11","Width_cm":"74.93","Height_cm":"46.34"} |
| lamp | Tansk | 30.48 | 30.48 | 165.1 | {"Length_cm":"30.48","Width_cm":"30.48","Height_cm":"165.1"} |
| bookshelf | Brock | 27.94 | 160.02 | 201.93 | {"Length_cm":"27.94","Width_cm":"160.02","Height_cm":"201.93"} |
| couch | Loafy | 95 | 227 | 83 | {"Length_cm":"95,"Width_cm":"227","Height_cm":"83"} |
| D s also |
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| label | wrangle_transform_nest |
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