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Extending HCL OneDB™Beyond standard relational database objects, HCL OneDB™ can be extended to handle specialized data types, access methods, routines, and other objects. HCL OneDB™ includes many built-in extensions that are fully integrated in the database server. HCL OneDB™ also provides DataBlade® modules, which are packages of extended database objects for a particular purpose and that are installed separately from the database server. Alternatively, you can create your own user-defined objects for HCL OneDB™.
Creating extensionsYou can create user-defined data types, routines, access methods, and other database objects to suit your needs. You can use application programming interfaces to write user-defined routines and applications that access data in HCL OneDB™ databases.
DataBlade® API Function ReferenceThe HCL OneDB™ DataBlade® API Function Reference describes the DataBlade® API functions and the subset of functions that the DataBlade® API supports.
Function descriptionsThis section gives comprehensive reference information about the functions that are valid within DataBlade® API modules. It lists the function descriptions in alphabetical order, with syntax, usage information, and return values for the functions.
The mi_new_var() functionThe mi_new_var() function creates a new varying-length structure for text data.

The mi_new_var() function

The mi_new_var() function creates a new varying-length structure for text data.

Syntax

mi_lvarchar *mi_new_var(data_len)
   mi_integer data_len;

data_len: The length of the data to store in the new varying-length structure.


Valid in client LIBMI application?	Valid in user-defined routine?
Yes	Yes

Usage

The mi_new_var() function is a constructor function for a varying-length structure. It allocates a varying-length structure with data_len bytes of data in its data portion. The function allocates memory for the varying-length structure that it returns. Therefore, you must use the mi_var_free() function to free this structure when it is no longer needed.

Server only: The mi_new_var() function allocates a new varying-length structure with the current memory duration.

Restriction: Do not use the DataBlade® API memory-management functions such as the mi_alloc() function to allocate a varying-length structure.

Return values

An mi_lvarchar pointer: A pointer to the new variable-length structure.
NULL: The function was not successful.