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readall

Read all data in DatabaseDatastore

Description

example

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.

Examples

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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

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

Output Arguments

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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