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问题

What is SQL?

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闪卡 1

问题

What is SQL?

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答案

SQL (Structured Query Language) is a programming language used to interact with a DBMS.

闪卡 2

问题

What does the SELECT command do in SQL?

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答案

The SELECT command retrieves data from a database table.

闪卡 3

问题

True or False? The WHERE clause in SQL is used to filter data based on a specified condition.

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答案

True. The WHERE clause in SQL is used to filter data based on a specified condition.

闪卡 4

问题

What is the purpose of the AND operator in SQL?

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答案

The AND operator combines multiple conditions in a WHERE clause.

闪卡 5

问题

What does the asterisk (*) wildcard represent in SQL?

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答案

The asterisk (*) wildcard is used to select all columns in a table.

闪卡 6

问题

What is the function of the ORDER BY clause in SQL?

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答案

The ORDER BY clause specifies how data is organised (sorted) when it is retrieved.

闪卡 7

问题

What does the SUM function do in SQL?

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答案

The SUM function adds up and outputs the sum of a field.

闪卡 8

问题

True or False? The COUNT function in SQL counts the number of fields in a table.

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答案

False. The COUNT function counts the number of rows which match the set criteria.

闪卡 9

问题

What is the purpose of the LIKE operator in SQL?

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答案

The LIKE operator is used for searching and matching data using wildcard characters.

闪卡 10

问题

How would you select all fields from a table named 'Customers' in SQL?

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答案

To select all fields from a table named 'Customers', use the command: SELECT * FROM Customers;