databases/
Tables, queries, indexes, transactions, storage engines and caching.
2 results
databases/the-n-1-query-problem-why-a-page-that-asks-the-database-501-questions.md
The N+1 query problem: why a page that asks the database 501 questions is slow
A page that lists authors and their books can quietly send one query per author. With 500 authors that is 501 trips to the database, and…
databases/sql-null-why-two-people-vanish-from-both-your-queries.md
SQL NULL: why two people vanish from both your queries
Two people have no age in your table. You ask for everyone older than 30, then for everyone not older than 30, and the two lists add up to…