Default field lengths for address fields in databases

Standard lengths for address fields in databasesToday, we will dive into some more theoretical stuff. The topic of this article will be field lengths of database fields for addresses. For every second database I create, I am faced with the same problem: How long / “big” do I actually make the database fields for addresses? So fields, such as first name, surname, street, e-mail address, etc.
So far I have oriented myself to given requirements or old databases. But now I wanted to work up the topic once for all right. So the question is: Is there actually a standard for address field lengths?
Looking for standards for address field lengths
A search for “address field lengths for databases” spits a huge amount of hits. Unfortunately there are only opinions and experiences everywhere. […]

Hot to show MySQL database size via SQL statement

Calculate MySQL database size via SQL statementToday, there is only a very short article with an SQL statement which allows you to display the size of a MySQL database, as well as the description of how to read out the database size via phpMyAdmin. Let’s start with the SQL statement. To display the size of a particular MySQL database in MegaByte (MB), use the following SQL command:

SELECT table_schema,
sum( data_length + index_length ) / 1024 / 1024 "Database Size in MB"
FROM information_schema.TABLES WHERE table_schema="{my_database_name}" GROUP BY table_schema

However, within the statement, before the execution, the placeholder {my_database_name} must be replaced by the name of the database whose size is to be determined. If the size of all database should be displayed on the MySQL server, the where clause can be omitted. […]