SQL Interview Questions #235: Is the index fit for queries?

SQL code copied to buffer

Task 235:

Is the following index a good fit for both queries?
| CREATE INDEX tbl_idx ON tbl (a, b);

| SELECT * FROM tbl
| WHERE a = 38 AND b = 1;

| SELECT * FROM tbl
| WHERE b = 1;
Source: The 3-Minute SQL Indexing Quiz

Good fit: No need to change anything.

Bad fit: Changing the index or query could improve performance.

Mark all correct answers and click the "Check!" button

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