Indexed column with function
Multiple choice questionThe following two queries produces the same results. The first uses LIKE and the second uses function LEFT. What is the best performing query, given that the column "title" is...
View ArticleOptimize queries that refer to nullable columns
True/false questionIs it True or False that it is harder for MySQL to optimize queries that refer to null-able columns.
View ArticleMySQL varchar amount of space
Multiple choice questionStoring the value 'hello world' requires the same amount of space in a VARCHAR(11) and a VARCHAR(255) column. Is there any advantage to using the shorter column?
View ArticleUsing index scans for sorts
Multiple choice questionGiven a UNIQUE KEY: my_key (a_field, b_field, c_field). Which of the following queries will use the key in order to sort the results?
View ArticleMySQL Range Condition
Multiple choice questionRange Condition makes MySQL ignore any further columns in the index. Which from the following MySQL queries is considered a Range Condition in MySQL?
View ArticleMySQL Blob and Text types
Multiple choice questionWhat is true about MySQL Blob and Text types?
View ArticleJoin Decomposition
Multiple choice questionJoin decomposition is a process of decomposing a join: running its single table queries parts and then composing the results at the application side. Can join decomposition give...
View ArticleMySQL Performance Quiz
Questions:12Attempts allowed:UnlimitedAvailable:AlwaysPass rate:75 %Backwards navigation:AllowedTake this MySQL performance quiz. MySQL Query and index optimization are the first and most important...
View Article