isopen
Determine if database connection is open
Syntax
Description
Examples
Determine If Database Connection Is Open
Connect to a Microsoft® SQL Server® database and verify the database connection. Then, import data from the database into MATLAB®. Determine the highest unit cost among the retrieved products in the table. Close the database connection.
Create an ODBC database connection to a Microsoft® SQL Server® database with Windows® authentication. Specify a blank user name and password. The database contains the table productTable
.
datasource = 'MS SQL Server Auth'; conn = database(datasource,'','');
Check the database connection. If the Message
property is empty, the connection is successful.
conn.Message
ans = []
Determine if the database connection is open. The isopen
function returns the numeric scalar 1
, which means the database connection is open.
i = isopen(conn)
i = 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.
selectquery = 'SELECT * FROM productTable ORDER BY productNumber';
data = select(conn,selectquery);
Display the first three rows of data.
data(1:3,:)
ans = 3×5 table productNumber stockNumber supplierNumber unitCost productDescription _____________ ___________ ______________ ________ __________________ 1 4.0035e+05 1001 14 'Building Blocks' 2 4.0031e+05 1002 9 'Painting Set' 3 4.01e+05 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 numeric scalar 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 = 0
Input Arguments
conn
— Database connection
connection
object
Database connection, specified as an ODBC connection
object or JDBC connection
object created using the
database
function.
Version History
Introduced in R2015b
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