多項選擇題

Which three statements are characteristic of the MEMORY storage engine?（）

A.It can support transactions
B.Table contents are not saved if the server is restarted
C.It cannot contain text or BLOB columns
D.It can support foreign keys
E.Each table is represented on disk as an.frm file
F.Each table has a corresponding.MYI and .MYD file

你可能感興趣的試題

多項選擇題

Consider typical High Availability (HA) solutions that do not use shared storage. Which three HA solutions do not use shared storage?（）

A.Mysql NDB Cluster
B.Mysql Replication
C.Distributed Replicated Block Device (DRBD) and Mysql
D.Windows Cluster and Mysql
E.Solaris Cluster and Mysql

單項選擇題

Consider the query:
Mysql＞ SET @run = 15;
Mysql＞ EXPLAIN SELECT objective, stage, COUNT (stage)
FROM iteminformation
WHERE run=@run AND objective=’7.1’
GROUP BY objective,stage
ORDER BY stage;

The iteminformation table has the following indexes;
Mysql＞ SHOW INDEXES FROM iteminformation:

This query is run several times in an application with different values in the WHERE clause in a growing data set.
What is the primary improvement that can be made for this scenario?（）

A.Do not pass a user variable in the WHERE clause because it limits the ability of the optimizer to use indexes
B.Add an index on the objective column so that is can be used in both the WHERE and GROUP BY operations
C.Drop the run_2 index because it has caused a conflict in the choice of key for this query
D.Execute the run_2 index because it has caused a conflict in the choice of key for this query
E.Add a composite index on (run,objective,stage) to allow the query to fully utilize an index

日韩欧美亚洲 _ 欧美亚洲一区 _ 日本亚洲欧美 _ 亚洲精品欧美 国产白袜脚足J棉袜在线观看_亚洲熟妇av一区二区三区_久久天天躁狠狠躁夜_精品众筹模特私拍在线

Which three statements are characteristic of the MEMORY storage engine?（）

你可能感興趣的試題

Consider typical High Availability (HA) solutions that do not use shared storage. Which three HA solutions do not use shared storage?（）

日韩欧美亚洲 _ 欧美亚洲一区 _ 日本亚洲欧美 _ 亚洲精品欧美国产白袜脚足J棉袜在线观看_亚洲熟妇av一区二区三区_久久天天躁狠狠躁夜_精品众筹模特私拍在线