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Basic SQL and String Reverse
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Basic SQL and String Reverse

EasySQL · PostgreSQL

Problem

Costar property search data includes short text values that require validation during ingestion and transformation testing. Write a PostgreSQL query that reverses each value in the string_tests table and verifies the result against the stored expected value.

Requirements

  1. Return each row's identifier, original text, reversed text, expected reversed text, and a Boolean validation result.
  2. Treat two NULL values as a valid match, preserve empty strings, and order the output by string_id.

Schema

string_tests
ColumnTypeDescription
string_idPKINTUnique test row identifier
input_textVARCHAR(100)Text value to reverse
expected_reverseVARCHAR(100)Expected reversed text used for validation
Tablesstring_tests
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