Why is a normal query for MYSQL so slow? Solve.

there are only 42 pieces of data in the table, ordinary SQL statements, no index and so on, and the table structure has not changed by default. Why the query speed is so slow.

select
articleId,
CODE,
articleTitle,
articleImg,
articleKeyword,
articleAbstract,
articleDetail,
creationtime,
updatetime,
articleAuthor,
accessNum,
STATUS,
articleDate,
isDeleted,
thumbsNum,
parent
from
article

it took more than 30 seconds to check. I want to know why this happened. No, no, no. I don"t know much about the database.

Mysql

Jan.15,2022

code staus is the keyword of mysq (code is sure, status is not). Add ``(the key below esc) to the query, and the query statements are automatically marked blue. It is recommended not to use this as the field name

several possibilities that can be thought of:

select happens to have a lock. Lock waiting. Check the slow log to see whether it is a lock waiting
the machine configuration is too poor, especially the IO performance of the hard disk. Type out the machine configuration to see
there is a problem with the permissions table. Permissions will be checked when the table is opened
there is a problem with the database installation

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MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1e3f119-64e1e.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1e3f119-64e1e.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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