Section 1 - Instruction

You've learned about the four stages of the SQL engine: parsing, planning, optimization, and execution. Now let's practice identifying which stage is responsible for different tasks.

This will help you diagnose query issues more effectively.

Engagement Message

Ready to put your knowledge to the test?

Section 2 - Practice

Type

Multiple Choice

Practice Question

A user writes UPDATE users SET name = 'Alex' WHER id = 10;. The query fails immediately. Which stage of the SQL engine most likely caught this error?

A. Parsing (due to the syntax error 'WHER') B. Planning (it couldn't find the 'id' column) C. Optimization (it couldn't find a good index) D. Execution (the row with id 10 doesn't exist)

Suggested Answers

  • A - Correct
  • B
  • C
  • D
Section 3 - Practice

Type

Sort Into Boxes

Practice Question

Sort these engine tasks into the correct stage.

Labels

  • First Box Label: Parsing
  • Second Box Label: Optimization

First Box Items

  • Check syntax
  • Verify keywords
  • Identify typos

Second Box Items

  • Choose best index
  • Analyze query cost
  • Find fastest path
Section 4 - Practice

Type

Fill in The Blanks

Markdown With Blanks

Fill in the blanks to describe the SQL engine's process.

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