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Client APIs and toolsYou can use the HCL OneDB™ implementation of client APIs to develop applications for HCL OneDB™ database servers.
ESQL/C GuideThe HCL OneDB™ ESQL/C Programmer's Manual explains how to use , the HCL OneDB™ implementation of Embedded Structured Query Language (SQL) for C (ESQL/C), to create client applications with database-management capabilities.
What is HCL OneDB™ ESQL/C?
Opaque data typesThese topics explain how to use the lvarchar, fixed binary, and var binary data types to access an opaque data type from the program. Use these data types to represent an opaque data type as it is transferred to and from HCL OneDB™.
Access predefined opaque data types

Access predefined opaque data types

HCL OneDB™ implements several built-in data types as predefined opaque data types. These data types are opaque data types for which support functions and the database definition are provided. For example, the smart-large-object data types, CLOB and BLOB, as an opaque data type called clob and blob are implemented. uses the ifx_lo_t structure, called an LO-pointer, to access the smart large objects. This structure is defined in the locator.h header file.

Therefore, you declare host variables for database columns of type CLOB or BLOB as a fixed binary host variable, as follows:

EXEC SQL include locator;
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EXEC SQL BEGIN DECLARE SECTION;
   fixed binary 'clob' ifx_lo_t clob_loptr;
   fixed binary 'blob' ifx_lo_t blob_loptr;
EXEC SQL END DECLARE SECTION;
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EXEC SQL select blobcol into :blob_loptr from tab1;