In mysql, you can use the SELECT statement to query the first column of data. This statement can query the data and output the results according to the field name of the specified column. You only need to set the field name after the "SELECT" keyword. It can be the first column field name that needs to be searched; the syntax is "SELECT first column field name FROM table name;".
The operating environment of this tutorial: windows7 system, mysql8 version, Dell G3 computer.
In mysql, you can use the SELECT statement to query the first column of data.
Use the SELECT statement to query data and output the results based on the field names of the specified columns.
The field name after the SELECT keyword is the field that needs to be searched. If you forget the field names, you can use the DESC command to see the structure of the table.
The syntax format of the first column field in the query table is:
SELECT 第一列字段名 FROM 表名;
Example:
Query the names of all students in the name column in the tb_students_info table
SELECT name FROM tb_students_info;
The output will show all the data under the name field in the tb_students_info table:
Note:
Can be obtained using the SELECT statement For data in multiple fields, you only need to specify the field name to be searched after the keyword SELECT. Different field names are separated by commas ",". There is no need to add a comma after the last field. The syntax format is as follows:
SELECT <字段名1>,<字段名2>,…,<字段名n> FROM <表名>;
Example: Get the three columns of id, name and height from the tb_students_info table
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