主要内容

isopen

Determine if MySQL native interface database connection is open

Description

i = isopen(conn) returns 1 if the MySQL® native interface database connection is open and 0 if it is closed or invalid.

example

Examples

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Connect to a MySQL® database using the MySQL native interface and verify the database connection. Then, import data from the database into MATLAB® using the database table productTable. Determine the highest unit cost among the retrieved products in the table. Close the database connection and ensure that the connection is closed.

Create a MySQL native interface database connection using a data source, user name, and password. The MySQL database contains the table productTable.

datasource = "MySQLNative";
username = "root";
password = "matlab";
conn = mysql(datasource,username,password);

Determine if the database connection is open. The isopen function returns the logical 1, which means the database connection is open.

i = isopen(conn)
i = logical
   1

Select all the data from productTable and sort it by the product number. data is a table containing the imported data that results from executing the SQL SELECT statement.

sqlquery = "SELECT * FROM productTable ORDER BY productNumber";
data = fetch(conn,sqlquery);

Display the first three rows of data.

head(data,3)
ans=3×5 table
    1    400345    1001    14    "Building Blocks"
    2    400314    1002     9       "Painting Set"
    3    400999    1009    17             "Slinky"

Determine the highest unit cost in the table.

max(data.unitCost)
ans = 
24

Close the database connection.

close(conn)

Determine if the database connection is closed. The isopen function returns the logical 0, which means the database connection is closed. If the database connection is invalid, the isopen function returns the same result.

i = isopen(conn)
i = logical
   0

Input Arguments

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MySQL native interface database connection, specified as a connection object. Starting in R2024a, it is recommended that you use setSecret and getSecret to store and retrieve your credentials for databases that require authentication. For more details, refer to this example.

Version History

Introduced in R2020b