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SQLBinary[data]

represents raw binary data that can be stored in a database.

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DatabaseLink`
DatabaseLink`

SQLBinary

SQLBinary[data]

represents raw binary data that can be stored in a database.

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范例

基本范例  (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:

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

Create a table with a column to store binary data:

Wolfram Language code: SQLCreateTable[conn, SQLTable["BINTABLE"], {SQLColumn["BINCOL", "DataTypeName" -> "BINARY", "DataLength" -> 5000]}];

Generate an image:

Wolfram Language code: plot = Plot[Sin[x], {x, 0, 2 Pi}]

Represent the image as a string in GIF format:

Wolfram Language code: gif = ExportString[plot, "GIF"];

Display the first few characters of the string:

Wolfram Language code: StringTake[gif, 100]

Convert the string into a list of bytes wrapped in SQLBinary:

Wolfram Language code: byteData = SQLBinary[ToCharacterCode[gif]];

Insert the data:

Wolfram Language code: SQLInsert[conn, "BINTABLE", {"BINCOL"}, {byteData}];

Retrieve the data:

Wolfram Language code: data = SQLSelect[conn, "BINTABLE"];

Convert the data back into a string:

Wolfram Language code: gifData = FromCharacterCode[ data[[1, 1, 1]] ];

Display the imported image:

Wolfram Language code: ImportString[gifData, "GIF"]
Wolfram Language code: SQLDropTable[conn, "BINTABLE"];
Wolfram Language code: CloseSQLConnection[conn];