Arrays

RDM allows integer or real type data columns of a table to be defined as one-dimendional arrays.

The following CREATE TABLE examples illustrate the use of ARRAY types:

Example 1

CREATE TABLE sale_emp (
    name            char(50),
    pay_by_quarter  integer array[4]
);

Snippet from the generated C structure from rdm-compile tool using --c-structs option.

/** \brief struct definition for table SALE_EMP */
typedef struct SALE_EMP_S
{
    char NAME[201];
    int32_t PAY_BY_QUARTER[4];
    RDM_HAS_VALUE_T _NAME_has_value;
    RDM_HAS_VALUE_T _PAY_BY_QUARTER_has_value;
} SALE_EMP;

The above command will create a table named SALE_EMP with a column of type CHAR (NAME) and a one-dimensional array of type INTEGER (PAY_BY_QUARTER), which represents the employee's salary by quarter for 4 quarters.

An array is a considered a single field (or column) so, either all dimensions are NULL or they all have a value.

Arrays are used for defining the dimensions of an R-tree index. For more information, refer to the R-tree Index Overview section.