In a design situation, there are multiple character sets that can properly encode your data.
Which three should influence your choice of character set?
A.
Disk usage when storing data
B.
Syntax when writing queries involving JOINS
C.
Comparing the encoded data with similar columns on other tables
D.
Memory usage when working with the data
E.
Character set mapping index hash size
Explanation:
what about A not C (ADE???)
C,D,E… Not A because disc size is least of problems.
ABC
The storage space required for a MySQL CHAR column is determined by the maximum number of characters and the column’s character set. For most (but not all) character sets, each character takes one byte of storage. When using UTF-8, each character requires three bytes. You can find the number of bytes needed per character in a given character set by checking the Maxlen column in the output of SHOW CHARACTER SET.
http://dev.mysql.com/doc/ndbapi/en/ndb-start-mysql-ndb-mapping.html
I think that there’s no RIGHT three.
There’s definitely a WRONG one, in my opinion, and that’s B (syntax for JOINs). The SYNTAX for the queries will be identical regardless of character-set.
While some UTF-8 characters (‘normal’ english) can occupy a single byte, many unusual or non-English characters take 3 or more bytes, so MEMORY (D) and DISK (A) concerns are valid.
But if the question is asking ‘your choice of character set” then B is out, and C is sort of out since all tables would be the same character set.
So, I am saying A, D and E as the right one.
A, C, D
I think answer would be: A, C, D
what’s the right answer ?
CDE