2. Then enter the information of the database and click the Connect button in the lower left corner of the interface to connect to the database.
3. After connecting to the database, enter the console of the database management software. The currently logged-in users, databases and database tables are displayed in the form of directories on the left side of the console. There are two blank rectangular boxes on the right side of the directory from top to bottom. The above is the input box of SQL query language, and the following is the result of the query.
4. Sometimes a database IP creates multiple databases. Before querying, you need to use data to select the database to be operated in the directory on the left side of the console, and then query.
5. The rectangular blank input box of SQL is mentioned above. Now let's query the database table. If you want to query all the information in a table, you can enter: SELECT * FROM TABLE_Name.
6. Query a piece of data in the table: select * from table _ name where ID = xxxx? Please note that the only key in the id selection table is the field used to identify this piece of data different from other data.
Displays the data information of the field: for example, name.
SELECT name FROM Table_Name where id=XXXX?
7. When using, you need to make statistics on the data in a table. You can use:
SELECT COUNT(*) FROM Tabele_Name
Statistical data of a certain condition: the number of all records in the age field 16 years old in the following statistical table.
SELECT COUNT(*)FROM tab ele _ Name where age = 16？
Multi-conditional data: According to the statistics in the following figure, the age field is 16 years old, and the class is Class 3.
SELECT COUNT(*) FROM Tabele_Name, where age= 16 and class=3.