PostgreSQL — JOINs

1 PostgreSQL SELECT with ILIKE Easy 2 PostgreSQL JOIN with alias #1 Hard 3 PostgreSQL JOIN with alias #2 Medium 4 PostgreSQL JOIN with alias #3 Medium 5 PostgreSQL JOIN with alias #4 Hard 6 PostgreSQL JOIN with alias #5 Medium 7 PostgreSQL JOIN with alias #6 Medium 8 PostgreSQL JOIN with alias #7 Hard 9 PostgreSQL JOIN with alias #8 Medium 10 PostgreSQL JOIN with alias #9 Medium 11 PostgreSQL JOIN with alias #10 Hard 12 PostgreSQL JOIN with alias #11 Medium 13 PostgreSQL JOIN with alias #12 Medium 14 PostgreSQL JOIN with alias #13 Hard 15 PostgreSQL JOIN with alias #14 Medium 16 PostgreSQL JOIN with alias #15 Medium 17 PostgreSQL JOIN with alias #16 Hard 18 PostgreSQL JOIN with alias #17 Medium 19 PostgreSQL JOIN with alias #18 Medium 20 PostgreSQL JOIN with alias #19 Hard 21 PostgreSQL JOIN with alias #20 Medium 22 PostgreSQL JOIN with alias #21 Medium 23 PostgreSQL JOIN with alias #22 Hard 24 PostgreSQL JOIN with alias #23 Medium 25 PostgreSQL JOIN with alias #24 Medium 26 PostgreSQL JOIN with alias #25 Hard 27 PostgreSQL JOIN with alias #26 Medium 28 PostgreSQL JOIN with alias #27 Medium 29 PostgreSQL JOIN with alias #28 Hard 30 PostgreSQL JOIN with alias #29 Medium 31 PostgreSQL JOIN with alias #30 Medium 32 PostgreSQL JOIN with alias #31 Hard 33 PostgreSQL JOIN with alias #32 Medium 34 PostgreSQL JOIN with alias #33 Medium 35 PostgreSQL JOIN with alias #34 Hard 36 PostgreSQL JOIN with alias #35 Medium 37 PostgreSQL JOIN with alias #36 Medium 38 PostgreSQL JOIN with alias #37 Hard 39 PostgreSQL JOIN with alias #38 Medium 40 PostgreSQL JOIN with alias #39 Medium 41 PostgreSQL JOIN with alias #40 Hard 42 PostgreSQL JOIN with alias #41 Medium 43 PostgreSQL JOIN with alias #42 Medium 44 PostgreSQL JOIN with alias #43 Hard 45 PostgreSQL JOIN with alias #44 Medium 46 PostgreSQL JOIN with alias #45 Medium 47 PostgreSQL JOIN with alias #46 Hard 48 PostgreSQL JOIN with alias #47 Medium 49 PostgreSQL JOIN with alias #48 Medium 50 PostgreSQL JOIN with alias #49 Hard