SQL

Extract measurements without guessing their type

BOTIE

Read the top-level temperature only from valid JSON numeric properties. Produce NULL for invalid text, missing properties, JSON null, strings or booleans.
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Context for this challenge

Read the top-level temperature only from valid JSON numeric properties. Produce NULL for invalid text, missing properties, JSON null, strings or booleans.

A sensor import now mixes numeric readings with strings and malformed messages.

Inspect the component calculation
Read a numeric JSON property(
  JSON records: JSON payload records
  JSON text field: payload
  Top-level property: temperature
  Numeric field: temperature
)
Examples and results
JSON payload records
[
  {
    "record_id": 1,
    "payload": "{\"temperature\":42}"
  },
  {
    "record_id": 2,
    "payload": "{\"temperature\":\"42\"}"
  },
  {
    "record_id": 3,
    "payload": "{}"
  },
  {
    "record_id": 4,
    "payload": "broken"
  },
  {
    "record_id": 5,
    "payload": "{\"temperature\":true}"
  }
]
Required result
[
  {
    "record_id": 1,
    "payload": "{\"temperature\":42}",
    "temperature": 42
  },
  {
    "record_id": 2,
    "payload": "{\"temperature\":\"42\"}",
    "temperature": null
  },
  {
    "record_id": 3,
    "payload": "{}",
    "temperature": null
  },
  {
    "record_id": 4,
    "payload": "broken",
    "temperature": null
  },
  {
    "record_id": 5,
    "payload": "{\"temperature\":true}",
    "temperature": null
  }
]
JSON payload records
[
  {
    "record_id": 4,
    "payload": "{\"temperature\":null}"
  },
  {
    "record_id": 1,
    "payload": "[1,2]"
  }
]
Required result
[
  {
    "record_id": 4,
    "payload": "{\"temperature\":null}",
    "temperature": null
  },
  {
    "record_id": 1,
    "payload": "[1,2]",
    "temperature": null
  }
]
Try a fresh construction

This clears this draft, including its undo history. Earlier successful attempts stay recorded. Build again without opening hints to record an independent attempt.

Stuck? Inspect a worked construction

The tools below form one possible solution. You can assemble it, follow its signals, and undo that change to return to your own construction.

Assumptions and test precision

The workshop uses finite JavaScript numbers and top-level JSON properties. Units, physical ranges and duplicate-key policy require separate ingestion validation. Numerical tests allow a difference of 0.001. Lists and structures must also have the right shape.

Your last tested pieces can start the full construction. An existing draft there keeps its own pieces.

A mixed new batch contains a real zero and several lookalikes

This check uses the pieces from “Retain known numeric extractions”.

BOTIE

Keep finite numeric temperature properties only. The boolean false, string "5.5", array and malformed text do not satisfy that type contract.
JSON payload records
[
  {
    "record_id": 12,
    "payload": "{\"temperature\":5.5}"
  },
  {
    "record_id": 10,
    "payload": "{\"temperature\":0}"
  },
  {
    "record_id": 11,
    "payload": "{\"temperature\":false}"
  },
  {
    "record_id": 13,
    "payload": "{\"temperature\":\"5.5\"}"
  },
  {
    "record_id": 14,
    "payload": "[5.5]"
  },
  {
    "record_id": 15,
    "payload": "{"
  }
]

Use a number, text, or an array matching the requested result. For a matrix, put each row in brackets. Saving your prediction runs your current construction on these inputs and checks the earlier examples too.

Build a construction in the workspace above first. This case will test those pieces.

Which checks would follow type extraction before a numeric value could be accepted as a physical temperature?

Validity, type and physical plausibility are separate boundaries. Keep rejection evidence instead of manufacturing zero readings.

The workshop uses finite JavaScript numbers and top-level JSON properties. Units, physical ranges and duplicate-key policy require separate ingestion validation.

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