mysql – how many columns is too many?

by

It’s considered too many once it’s above the maximum limit supported by the database.

The fact that you don’t need every column to be returned by every query is perfectly normal; that’s why SELECT statement lets you explicitly name the columns you need.

As a general rule, your table structure should reflect your domain model; if you really do have 70 (100, what have you) attributes that belong to the same entity there’s no reason to separate them into multiple tables.

More Related Contents:

  1. MySQL Insert query doesn’t work with WHERE clause
  2. Delete from two tables in one query
  3. PostgreSQL GROUP BY different from MySQL?
  4. GROUP BY behavior when no aggregate functions are present in the SELECT clause
  5. Fulltext Search with InnoDB
  6. MySQL’s now() +1 day
  7. Rewriting mysql select to reduce time and writing tmp to disk
  8. How do I convert from BLOB to TEXT in MySQL?
  9. Can you access the auto increment value in MySQL within one statement?
  10. Which SQL query is better, MATCH AGAINST or LIKE?
  11. MySQL equivalent of DECODE function in Oracle
  12. How do you version your database schema? [closed]
  13. Can a stored procedure/function return a table?
  14. MySQL, Get users rank
  15. Mysql: how to select groups having certain values?
  16. How to fill date gaps in MySQL?
  17. Boolean vs tinyint(1) for boolean values in MySQL
  18. Selecting all corresponding fields using MAX and GROUP BY
  19. MySQL: “The SELECT would examine more than MAX_JOIN_SIZE rows”
  20. Function for week of the month in mysql
  21. Find rows that have the same value on a column in MySQL
  22. what is the difference between GROUP BY and ORDER BY in sql
  23. Two single-column indexes vs one two-column index in MySQL?
  24. VARCHAR as foreign key/primary key in database good or bad?
  25. MySQL SELECT x FROM a WHERE NOT IN ( SELECT x FROM b ) – Unexpected result
  26. How do I create a table alias in MySQL
  27. MySql bulk load command line tool
  28. ALTER TABLE without locking the table?
  29. MySQL: Typecasting NULL to 0
  30. How to get the byte size of resultset in an SQL query?

Leave a Comment