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Update Negative Numbers to Zero
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Update Negative Numbers to Zero

EasySQL · PostgreSQL

Problem

How would you update a list of numbers in SQL?

Use the number_list table. Update every negative number_value to 0; leave zero, positive, and NULL values unchanged.

Output

  1. Return one row for each updated record, with columns id and number_value.
  2. Ignore rows where number_value is NULL.
  3. Order the results by id ascending.

Schema

number_list
ColumnTypeDescription
idPKINTEGERUnique identifier for the list entry
number_valueINTEGERNumber that may need to be updated
Tablesnumber_list
Interviewer

Whenever you're ready, walk me through your approach or go straight to the code. The requirements and the one table are in the Question tab.

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