Contents
How to select count on a billion records table?
I am writing a simple query which is Select count (*) from wsh_exceptions. Currently this table contains 1,091,130,564 records. So because of this more number of records in this table, select count (*) is taking so much time. Alternately I am using num_rows column from dba_tables to know the number of rows.
Which is the best database to store billions of rows?
They are quite good at handling record counts in the billions, as long as you index and normalize the data properly, run the database on powerful hardware (especially SSDs if you can afford them), and partition across 2 or 3 or 5 physical disks if necessary.
How big are the rows in Stack Overflow?
Very few people work at the multi-billion row set size, and most times that I see a request like this on stack overflow, the data is no where near the size it is being reported as.
What’s the name of the next number after trillion?
What Comes After Trillion? What’s after trillion? Trillion is a 1 with 12 zeros after it, and it looks like this: 1,000,000,000,000. The next named number after trillion is quadrillion, which is a 1 with 15 zeros after it: 1,000,000,000,000,000.
Which is the fastest way to count rows in a table?
How about if I just want to know if there is anything in the table at all? (e.g., count > 0?) The best way is to make sure that you run SELECT COUNT on a single column ( SELECT COUNT (*) is slower) – but SELECT COUNT will always be the fastest way to get a count of things (the database optimizes the query internally).
How to count the exact number of rows?
Takes a while for a table with large number of rows, but the row count is very exact. Console output: Affected rows: 0 Found rows: 1 Warnings: 0 Duration for 1 query: 0.250 sec Summary: Row count is not exact.
How to select count of rows in another table?
I think the comment by @intgr in another answer is so valuable I’m putting forward this as an alternate answer as this method allows you to filter the calculated column efficiently.