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Task 89: 
To improve the performance of analytical queries, create an index named island_ix on the island column of the penguins table.

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Use SQLite syntax to write your answer. Descriptions of tables are provided at the bottom of the screen.

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Querynomicon (SQLite)

A compact database for learning the basics of SQL.

The Querynomicon database tables:

department - table of departments.
  • identDepartment ID
  • nameDepartment name
  • buildingBuilding name
ident name building
gen Genetics Chesson
little_penguins - table of little penguins.
  • speciesPenguin species
  • islandIsland of residence
  • bill_length_mmBill length, mm
  • bill_depth_mmBill depth, mm
  • flipper_length_mmFlipper length, mm
  • body_mass_gBody mass, g
  • sexSex
species island bill_length_mm bill_depth_mm flipper_length_mm body_mass_g sex
Gentoo Biscoe 52.1 17 230 5550 MALE
penguins - table of penguins.
  • speciesPenguin species
  • islandIsland of residence
  • bill_length_mmBill length, mm
  • bill_depth_mmBill depth, mm
  • flipper_length_mmFlipper length, mm
  • body_mass_gBody mass, g
  • sexSex
species island bill_length_mm bill_depth_mm flipper_length_mm body_mass_g sex
Gentoo Biscoe 52.1 17 230 5550 MALE
staff - table of employees.
  • identEmployee number
  • personalEmployee first name
  • familyEmployee last name
  • deptDepartment
  • ageAge
ident personal family dept age
7 Abram Chokshi gen 23
machine - table of machines.
  • identMachine ID
  • nameMachine name
  • detailsJSON with details
ident name details
1 WY401 {"acquired": "2023-05-01"}
2 Inphormex {"acquired": "2021-07-15", "refurbished": "2023-10-22"}
3 AutoPlate 9000 {"note": "needs software update"}
SQL in 10 Minutes a Day by Ben Forta
SQL in 10 Minutes a Day by Ben Forta
Whether you're an application developer, database administrator, web application designer, mobile app developer, or Microsoft Office users, a good working knowledge of SQL is an important part of interacting with databases. And Sams Teach Yourself SQL in 10 Minutes offers the straightforward, practical answers you need to help you do your job.