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SQLConnectionOpenQ[conn]

tests whether or not conn is a valid connection object.

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Basic Examples  
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DatabaseLink`
DatabaseLink`

SQLConnectionOpenQ

SQLConnectionOpenQ[conn]

tests whether or not conn is a valid connection object.

Details and Options

Examples

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Basic Examples  (1)

Wolfram Language code: Needs["DatabaseLink`"]

If you find that the examples in this section do not work as shown, you may need to install or restore the example database with the "DatabaseLink`DatabaseExamples`" package, as described in Using the Example Databases.

Open a connection to a sample database:

Wolfram Language code: conn = OpenSQLConnection["demo"]

Test the connection's validity:

Wolfram Language code: SQLConnectionOpenQ[conn]

Close the connection:

Wolfram Language code: CloseSQLConnection[conn];

Test the connection's validity again:

Wolfram Language code: SQLConnectionOpenQ[conn]

Properties & Relations  (1)

Wolfram Language code: Needs["DatabaseLink`"]

SQLConnectionOpenQ initiates no server communication, so a True result does not imply that queries may be issued on the connection. Use SQLConnectionUsableQ for this purpose:

Wolfram Language code: conn = OpenSQLConnection["demo"]

Test the connection:

Wolfram Language code: Through[{SQLConnectionOpenQ, SQLConnectionUsableQ}[conn]]

Since SQLConnectionUsableQ performs server communication, it will generally take longer than SQLConnectionOpenQ to evaluate:

Wolfram Language code: AbsoluteTiming[#[conn]]& /@ {SQLConnectionOpenQ, SQLConnectionUsableQ}

Close the connection:

Wolfram Language code: CloseSQLConnection[conn];