ConnectionString Property (BigQueryConnection)

Visual Basic
C#


'Declaration Public Shadows Property ConnectionString As String


public new string ConnectionString {get; set;}

Property Value

The connection string that includes the parameters needed to establish the initial connection. The default value is an empty string ("").

When ConnectionString property is assigned a value, connection closes. Many of the connection string values have corresponding properties. When the connection string is set, all of these properties are updated, except when an error is detected. In this case, none of the properties are updated. BigQueryConnection properties return only those settings contained in the ConnectionString.

Resetting the ConnectionString on a closed connection resets all connection string values (and related properties).

The connection string is parsed immediately after being set. If errors in syntax are found when parsing, a runtime exception, such as System.ArgumentException, is generated. Other errors can be found only when an attempt is made to Open the connection.

The ConnectionString is similar to an OLE DB connection string. Values may be delimited by single or double quotes, (for example, name='value' or name="value"). Either single or double quotes may be used within a connection string by using the other delimiter, for example, name="value's" or name= 'value"s', but not name= 'value's' or name= ""value"". All blank characters, except those placed within a value or within quotes, are ignored. Keyword value pairs must be separated by a semicolon (;). If a semicolon is part of a value, it also must be delimited by quotes. No escape sequences are supported. The value type is irrelevant. Names are not case sensitive. Arguments names may occur only once in the connection string.

The following table lists the valid names for values within the ConnectionString.

Name	Description
Authentication Type	Specifies the authentication method: UserAccount, ServiceAccount, or UserAccountInteractive. See AuthenticationType for more information.
Client Id	Specifies the OAuth 2.0 client ID of your application registered in the Google Cloud Console. Required for the UserAccount authentication method. For UserAccountInteractive, if it is not specified, the client ID of the Devart application is used.
Client Secret	Specifies the OAuth 2.0 client secret of your application registered in the Google Cloud Console. Required for the UserAccount authentication method. For UserAccountInteractive, if it is not specified, the client secret of the Devart application is used.
DataSet Id	Specifies the ID of the default dataset. If it is specified, metadata is retrieved only for this dataset.
Default Cloud Storage Bucket	Specifies the name of the Google Cloud Storage bucket that BigQueryLoader uses by default to store data temporarily before loading it to Google BigQuery.
Enlist	Determines whether the connection is automatically enlisted in the current transaction context (TransactionScope). The default value is true.
License Key	Specifies the license key of dotConnect for Google BigQuery. It is required when the license is not registered on the machine, for example, in build or deployment scenarios.
Primary Key Column	Specifies a comma-separated list of columns that are considered primary key columns for tables that have no declared primary key. Specify a column name for all tables, or table.column for a specific table.
Project Id	Specifies the ID of the Google Cloud project to connect to.
Refresh Token	Specifies the OAuth 2.0 refresh token used for the UserAccount and UserAccountInteractive authentication methods.
ServiceAccount Json	Specifies the service account key for the ServiceAccount authentication method: either the content of the key JSON file or the path to this file.
Use Legacy SQL	Determines whether queries use the legacy SQL dialect of Google BigQuery instead of GoogleSQL. The default value is false.
Connection Lifetime	Determines the maximum time span (in seconds) a connection can remain in the pool: when a connection is returned to the pool, its creation time is compared with the current time, and the connection is destroyed if that time span exceeds the value specified by Connection Lifetime. The default value is 0 (connection always returns to pool).
Connect Timeout -or- Connection Timeout	Specifies the length of time (in seconds) to wait for a connection to the server before terminating the attempt and generating an error. The default value is 60.
Default Command Timeout	Specifies the time in seconds to wait while trying to execute a command before terminating the attempt and generating an error. A value of 0 indicates no limit.
Initialization Command	Specifies a data source-specific command to execute immediately after the connection is established.
Max Pool Size	Specifies the maximum number of connections allowed in the pool. Setting the Max Pool Size value of the ConnectionString can affect performance. The default value is 100.
Min Pool Size	Specifies the minimum number of connections allowed in the pool. The default value is 0.
Persist Security Info	Indicates if security-sensitive information, such as the password, is not returned as part of the connection if the connection is open or has ever been in an open state.
Pooling	Determines whether, by default, the BigQueryConnection object is drawn from the appropriate pool or is created and added to the appropriate pool, when set to true.
Proxy Host	Specifies the host name or IP address of proxy server.
Proxy Password	Specifies the password for the proxy server account.
Proxy Port	Specifies the port number of the proxy server. The default value is 3128.
Proxy User	Specifies the proxy server account name.
Run Once Command	Specifies a command to execute the first time the connection is opened. The command is not executed when the connection is retrieved from the connection pool.
Readonly	Determines whether the connection is read-only (allows only SELECT statements).
UTC Dates	Indicates whether all the datetime values retrieved from the data source are returned as UTC values or converted to local time, and whether date values, specified on the application side (for example, in SQL statements) are considered UTC or local. Default value is false.

The following example creates a BigQueryConnection and sets some of its properties in the connection string.

csharp


public void CreateBigQueryConnection() { string myConnString1 = @"Authentication Type=ServiceAccount;ServiceAccount Json=C:\keys\service-account.json;Project Id=your_project;DataSet Id=your_dataset;License Key=**********"; BigQueryConnection bigQueryConnection1 = new BigQueryConnection(myConnString1); bigQueryConnection1.Open(); }

public void CreateBigQueryConnection()
{
  string myConnString1 = 
     @"Authentication Type=ServiceAccount;ServiceAccount Json=C:\keys\service-account.json;Project Id=your_project;DataSet Id=your_dataset;License Key=**********";
  BigQueryConnection bigQueryConnection1 = new BigQueryConnection(myConnString1);
  bigQueryConnection1.Open();
}

Visual Basic


Public Sub CreateBigQueryConnection() Dim myConnString1 As String = _ "Authentication Type=ServiceAccount;ServiceAccount Json=C:\keys\service-account.json;Project Id=your_project;DataSet Id=your_dataset;License Key=**********" Dim bigQueryConnection1 As New BigQueryConnection(myConnString1) bigQueryConnection1.Open() End Sub

Public Sub CreateBigQueryConnection()
  Dim myConnString1 As String = _
      "Authentication Type=ServiceAccount;ServiceAccount Json=C:\keys\service-account.json;Project Id=your_project;DataSet Id=your_dataset;License Key=**********"
  Dim bigQueryConnection1 As New BigQueryConnection(myConnString1)
  bigQueryConnection1.Open()
End Sub

Reference

BigQueryConnection Class
BigQueryConnection Members
Open Method
BigQueryConnectionStringBuilder Class