SQL query data and sorting

I. SQL query data and sorting syntax

1. Query data syntax

Select: Query

The syntax is as follows:

(1) Use "Select" to query a field value

Select table fields from table name

(2) Use "Select" to query the values ​​of multiple fields (the fields should be separated by ",")

Select table field, table field, table field from table name

(3) Use "Select" to query the data of the entire table

Select * from table name

Note:

(1) We want to query multiple fields to be separated by ","

(2) To query the fields of multiple different tables, we also use "," to separate different table names

When processing the Select statement, our SQL server processes the From clause first, and then processes the Select clause. Even if the Select clause comes first, its processing order is the same

2. Sort the data

If we use the "Select" statement alone, the data found will not be automatically sorted, that is, "random".

But what if we want to sort the queried data?

order By: Sort

Ascending: asc

Reverse order: desc

The syntax is as follows:

Select table fields

from table name

order by table field desc

Note:

1. By default, our sorting is "ascending", so we can omit not write "asc"

Two, practice the truth

(1) Query example

This is the data for our entire table

Now we want to find the value in the "name" field (use "Select" to query the value of a field)

(2) Use "Select" to query the values ​​of multiple fields

(3) Use "Select" to query the data of the entire table

2. Data sorting example

1. Use ascending order: sort from small to large.

By default, our ascending "asc" can be omitted.

(2) Use "desc" to: arrange "from large to small"

This is what I understand about the usage of SQL****query statement and sorting syntax. If I misunderstand, please forgive me and correct me!thank you all.

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