Data Engineering Associate with Databricks Practice Exam

In SQL, how is a record updated based on a condition?

1. UPDATE students SET value = value + 1 WHERE name LIKE "T%"

2. UPDATE students WHERE name LIKE "T%" SET value + 1

3. MODIFY students VALUE = value + 1 WHERE name LIKE "T%"

4. CHANGE students SET value = value + 1 WHERE name = "T"

The correct answer is: UPDATE students SET value = value + 1 WHERE name LIKE "T%"

The correct answer utilizes the proper syntax for updating records in SQL. In SQL, the UPDATE statement is designed to modify existing records within a table. The essential components of the UPDATE statement include specifying the table to update (in this case, "students"), setting the new value for a specific column ("value = value + 1"), and including a condition to narrow down which records to update ("WHERE name LIKE 'T%'"). This condition indicates that only records where the "name" column starts with the letter 'T' will be modified. The use of the LIKE operator is appropriate here as it allows for pattern matching, making it possible to update multiple records that meet the condition. In contrast, the other statements do not conform to SQL syntax requirements. For example, one of the options fails to define the SET clause correctly before specifying the condition, and another option uses incorrect keywords and structure, which would result in a syntax error when executed. Therefore, the first choice correctly demonstrates the standard SQL approach for updating records conditionally.