Asked by: Odette Jungkunz
technology and computing databases

What is the use of explain in MySQL?

Last Updated: 2nd April, 2020

The EXPLAIN keyword is used throughout various SQL databases and provides information about how your SQL database executes a query. In MySQL, EXPLAIN can be used in front of a query beginning with SELECT , INSERT , DELETE , REPLACE , and UPDATE .

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In this manner, what is explain in MySQL?

The EXPLAIN statement provides information about how MySQL executes statements: EXPLAIN works with SELECT , DELETE , INSERT , REPLACE , and UPDATE statements. When EXPLAIN is used with an explainable statement, MySQL displays information from the optimizer about the statement execution plan.

Subsequently, question is, how do you use explain? The verb explain is not followed by object pronoun. It can't be followed by a pronoun like me, him, her, you or us that is the object of the verb, or the pronoun that receives the action of the verb. That's why “Can you explain me …?” is wrong. The verb explain has a very specific sentence pattern.

Besides, what is Key_len in MySQL explain?

mysql. According to MySQL website, the key_len column indicates the length of the key that MySQL decided to use. The length is NULL if the key column says NULL . Note that the value of key_len enables you to determine how many parts of a multiple-part key MySQL actually uses.

What is filtered in explain MySQL?

As described here in the MySQL docs: The filtered column indicates an estimated percentage of table rows that will be filtered by the table condition. That is, rows shows the estimated number of rows examined and rows × filtered / 100 shows the number of rows that will be joined with previous tables. As of MySQL 5.7.

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What is query explain with example?

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Where can I find explain plan in MySQL?

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What do you mean by query?

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What is analyze in MySQL?

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Even if you optimize your MySQL queries and fail to come up with a good database structure, your database performance can still halt when your data increases.
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How do I find the query plan in SQL Server?

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Can you explain me why?

So, when you ask "Can you explain it to me?", you are basically asking whether the opposite person is capable of explaining something. Could is a safe option and is more polite, so always go for could. By the way, it is explain to me (or better, explain it to me), not explain me.

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What is the meaning of example?

An example of something is a particular situation, object, or person which shows that what is being claimed is true. If you refer to a person or their behaviour as an example to other people, you mean that he or she behaves in a good or correct way that other people should copy.

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Is the a verb?

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Can you explain me or to me?

Explain to me. "me" is the indirect object. Intransitive verbs don't have objects, direct or indirect; they have complements. The prepositional phrase to me (where "me" is the object of the preposition "to") is a complement that modifies (completes the meaning of) the intransitive verb explain.

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How do you explain something in an essay?

Give your reader a reason to learn about your concept. Connect this information to something they already know, or give them a definition which either reverses their expectations or gives a new perspective or insight. Give a clear definition. Explain any unfamiliar terms or special vocabulary.