define is an operation that defines a data resource.
A select operation may not return any data resources but the define operation returns always the data resource that it defines.
This operation is used:
The define operations accept the following arguments.
Arguments | Mandatory | Definition |
---|---|---|
data-uri | only if data is not defined | The data uri is the location of the resource |
data | only if data-uri is not defined | The data as a list of records (the data are in the inline) |
data-definition | no | The data definition |
data-resources | to define more than one data resource (a list of inline data resources) |
This operation is only available as step in a pipeline pipeline (ie not in a tabli data command)
This is a first step (known as the supplier step) because it supplies data resources to the others operations in the pipeline.
Example: A color data resource with two columns and 3 records.
pipeline:
- name: "Define"
comment: "This operation define the tabular data resource named 'colors' with two columns"
operation: "define"
args:
data-resource:
data-definition:
logicalName: "colors"
columns: ["id","color"]
data:
- ["1", "blue"]
- ["2", "red"]
- ["3", "yellow"]
- name: "Print"
comment: "Print the colors resource"
operation: "print"
If you execute this pipeline
tabli flow execute pipeline/define_single.yml@howto
you will get the data of the colors data resource printed in a tabular format.
id color
-- ------
1 blue
2 red
3 yellow
Two inline data resources colors and characters
pipeline:
- name: 'Define'
operation: 'define'
args:
data-resources:
- data-definition:
logicalName: "colors"
columns: ["id","color"]
data:
- ["1", "blue"]
- ["2", "red"]
- ["3", "yellow"]
- data-definition:
logicalName: "characters"
columns:
- name: "id"
type: integer
- name: "name"
- name: "last_name"
data:
- [1, "Arnold","Schwarzy"]
- [2, "Don","Norman"]
- [3, "Dale","Carnegie"]
- [4, "Daniel","Kahneman"]