Check out example codes for "how to count number of rows in sql". It will help you in understanding the concepts better.
Code Example 1
SELECT COUNT(*) FROM dbo.bigTransactionHistory;
Code Example 2
/* COUNT() is a function that takes on the name of a clomn as an argument and counts the number of rows where the column is not null */ SELECT COUNT(column_name) FROM table_name;
Learn ReactJs, React Native from akashmittal.com