Main Content

readall

Read all data in DatabaseDatastore

Description

data = readall(dbds) returns all the data in the DatabaseDatastore object dbds, and resets the DatabaseDatastore to the point where no data has been read from it.

example

Examples

collapse all

Create a database connection using a JDBC driver. To create this connection, you must configure a JDBC data source. For more information, see the configureJDBCDataSource function. Then, create a DatabaseDatastore object and read all data stored in the object.

Create a database connection to the JDBC data source MSSQLServerJDBCAuth. This data source configures a JDBC driver to a Microsoft® SQL Server® database with Windows® authentication. Specify a blank user name and password.

datasource = "MSSQLServerJDBCAuth";
username = "";
password = "";
conn = database(datasource,username,password);

Create a DatabaseDatastore object using the database connection and an SQL query. This SQL query reads all data from the airlinesmall table.

sqlquery = 'select * from airlinesmall';

dbds = databaseDatastore(conn,sqlquery);

Read all data in the DatabaseDatastore object.

data = readall(dbds);

data contains the query results.

Display the first three rows of query results.

data(1:3,:)
ans =

  3×29 table

    Year    Month    DayofMonth    DayOfWeek    DepTime    CRSDepTime    ArrTime    CRSArrTime    UniqueCarrier    FlightNum    TailNum    ActualElapsedTime    CRSElapsedTime    AirTime    ArrDelay    DepDelay    Origin    Dest     Distance    TaxiIn    TaxiOut    Cancelled    CancellationCode    Diverted    CarrierDelay    WeatherDelay    NASDelay    SecurityDelay    LateAircraftDelay
    ____    _____    __________    _________    _______    __________    _______    __________    _____________    _________    _______    _________________    ______________    _______    ________    ________    ______    _____    ________    ______    _______    _________    ________________    ________    ____________    ____________    ________    _____________    _________________

    1987     10          28            3         1140         1140        1212         1215           'US'            262        'NA'             32                  35           'NA'         -3          0        'CLE'     'PIT'      105        'NA'      'NA'          0              'NA'             0            'NA'            'NA'          'NA'          'NA'               'NA'       
    1987     10           9            5         1155         1155        1250         1300           'US'            282        'NA'             55                  65           'NA'        -10          0        'ROC'     'LGA'      254        'NA'      'NA'          0              'NA'             0            'NA'            'NA'          'NA'          'NA'               'NA'       
    1987     10          22            4          715          715         807          803           'US'            304        'NA'             52                  48           'NA'          4          0        'DTW'     'PIT'      201        'NA'      'NA'          0              'NA'             0            'NA'            'NA'          'NA'          'NA'               'NA'       

Close the DatabaseDatastore object and the database connection.

close(dbds)

Input Arguments

collapse all

Datastore containing data in a database, specified as a DatabaseDatastore object created using the databaseDatastore function.

Output Arguments

collapse all

Query results, returned as a table of the records in the data set. Executing the SQL statement specified in the Query property of the DatabaseDatastore object creates the data set.

Version History

Introduced in R2014b

Go to top of page