92. Count Items in a CSV Field
MediumString Manipulationlengthreplace
SQLite has no array type, but you can count how many times a character appears with the length trick: length(s) - length(replace(s, ch, '')) is the number of occurrences of ch. For a comma-separated list the item count is the comma count plus one.
Task: each tags value is a non-empty comma-separated list. Return id, tags, and item_count — the number of items, computed as length(tags) - length(replace(tags, ',', '')) + 1. Order by id.
Output columns, in order: id, tags, item_count.
Tables
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Expected outputrows must come back in this order
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This is the result for the example data above. On Submit your query is graded against this example plus 4 hidden edge cases — 5test cases in all. A sloppy query that only fits the example won't pass.
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