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SQL programmingYou can use the HCL OneDB™ implementation of the SQL language to develop applications for HCL OneDB™ database servers.
Guide to SQL: SyntaxThe HCL OneDB™ Guide to SQL: Syntax describes the syntax of the statements, data types, expressions, operators, and built-in functions of the HCL OneDB™ dialect of the SQL language.
SQL statementsThis chapter describes the syntax and semantics of SQL statements that are recognized by HCL OneDB™.
UNLOAD statementUse the UNLOAD statement to write the rows retrieved by a SELECT statement to an operating-system file. The UNLOAD statement is an extension to the ANSI/ISO standard for SQL.
UNLOAD TO FileThe UNLOAD TO file, as specified by the filename parameter, receives the retrieved rows.
Unloading Simple Large Objects

Unloading Simple Large Objects

The database server writes BYTE and TEXT values directly into the UNLOAD TO file. BYTE values are written in hexadecimal dump format with no added blank spaces or new line characters. The logical length of an UNLOAD TO file containing BYTE data can therefore be long and difficult to print or edit.

If you are unloading files that contain simple-large-object data types, do not use characters that can appear in BYTE or TEXT values as delimiters in the UNLOAD TO file. See also the section DELIMITER Clause.

The database server handles any required code-set conversions for TEXT data. For more information, see the HCL OneDB™ GLS User's Guide.

If you are unloading files that contain simple-large-object data types, objects smaller than 10 kilobytes are stored temporarily in memory. You can adjust the 10-kilobyte setting to a larger setting with the DBBLOBBUF environment variable. BYTE or TEXT values larger than the default or the DBBLOBBUF setting are stored in a temporary file. For additional information about DBBLOBBUF, see the HCL OneDB Guide to SQL: Reference.