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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.
Data types and expressionsThese topics describe the data types and expressions that HCL OneDB™supports.
Data TypeThe Data Type segment specifies the data type of a column, of a component of a collection, of a field within a ROW type, of a routine parameter, or of a value returned by an expression or by a cast function. Use this segment whenever you see a reference to a data type in a syntax diagram.
User-Defined Data Type
Opaque Data Types

Opaque Data Types

An opaque data type is a user-defined data type that can be used in the same way as a built-in data type. To create an opaque type, you must use the CREATE OPAQUE TYPE statement. Because an opaque type is encapsulated, you create support functions to access the individual components of an opaque type. The internal storage details of the type are hidden or opaque.

For more information about how to create an opaque data type and its support functions, see HCL OneDB™ User-Defined Routines and Data Types Developer's Guide.

Because of the maximum row size limit of 32,767 bytes, when you create a new table, no more than approximately 195 columns can be varying-length opaque or distinct user-defined data types. (The same restriction applies to BYTE, TEXT, VARCHAR, LVARCHAR, NVARCHAR, and ROW type columns. See ROW Data Types for additional information about ROW data types.)