frequency of different types of join predicates
From: Bob Jenkins <bob_jenkins_at_burtleburtle.net>
Date: 23 Oct 2001 16:47:09 -0700
Message-ID: <a5d787df.0110231547.21794c4_at_posting.google.com>
Date: 23 Oct 2001 16:47:09 -0700
Message-ID: <a5d787df.0110231547.21794c4_at_posting.google.com>
What is the frequency of equijoins versus range scans versus likes? Which SQL predicates are most common?
I made a rough estimate by searching for them in catalog.sql and the
other .sql files in that directory. I screened out any rows with
comments (rem, /*, //), then got rid of the patterns :=, <<, >>, ->,
=>. I got rid of <=, >=, !=, <> before counting <, >, =. The counts
were:
11184 82.4% = 763 5.6% > 632 4.7% < 365 2.7% != 238 1.7% is null 131 0.9% like 119 0.9% is not null 73 0.5% >= 36 0.3% <> 27 0.2% <= 3457 := 958 (+) 115 => 58 -> 23 connect by 14 << 14 >>Received on Wed Oct 24 2001 - 01:47:09 CEST