Syntax - Advanced SQL Engine - Teradata Database

void
FNC_GetArrayTypeInfo ( ARRAY_HANDLE   aryHandle,
                       array_info_t  *arrayInfo,
                       bounds_t      *arrayScope)

ARRAY_HANDLE aryHandle

The handle to an ARRAY type that is defined to be an input parameter to an external routine.

array_info_t *arrayInfo

A pointer to the buffer that will hold the information about the ARRAY input parameter.

The array_info_t structure is defined in sqltypes_td.h as:

typedef struct array_info_t {
   int numDimensions;
   int totalNumElements;
   element_info_t elementInfo;
} array_info_t;

where:

• numDimensions = the number of dimensions defined for the ARRAY type.
• totalNumElements = the total number of elements (across all dimensions) defined for the ARRAY type. This is also known as the maximum cardinality of the ARRAY type.
• elementInfo = information about the elements of the ARRAY type. For details, see the description of the element_info_t structure that follows.

The element_info_t structure is defined in sqltypes_td.h as:

typedef struct element_info_t {
   dtype_et data_type;
   SMALLINT udt_indicator;
   CHARACTER udt_type_name[256];
   INTEGER max_length;
   SMALLINT total_interval_digits;
   SMALLINT num_fractional_digits;
   charset_et charset_code;
} element_info_t;

where:

• data_type = the data type of the elements of the ARRAY.
• udt_indicator= whether the element is a UDT.

  The possible values for udt_indicator are as follows:

  0 = not a UDT

  1 = structured UDT

  2 = distinct UDT

  3 = Teradata proprietary internal UDT

• udt_type_name = the UDT type name associated with the element if the element is a UDT.
• max_length = the maximum length in bytes of an element value.

  You can use max_length as the size in bytes of the buffer you need to allocate before you make a call to FNC_GetArrayElement to get the values of one element of an ARRAY.

• total_interval_digits = the precision value for certain element types. For example, the value n in a DECIMAL(n,m) type or in INTERVAL DAY(n) TO SECOND(m). The list of types that use this value is the same as that of attribute_info_t.total_interval_digits.
• num_fractional_digits = the precision or scale value for certain element types. For example, the value m in a DECIMAL(n,m) type or in INTERVAL DAY(n) TO SECOND(m). The list of types that use this value is the same as that of attribute_info_t.num_fractional_digits.
• charset_code = the server character set associated with the element if the element is a character type.

For more information about dtype_et, total_interval_digits, num_fractional_digits, or charset_et, see FNC_GetStructuredAttributeInfo.

bounds_t *arrayScope

An array of bounds_t structures that describes the scope of each dimension in an n-D ARRAY. If the ARRAY type is 1-D, then the default scope information for that single dimension (beginning with 1, ending with n, where n is the size of the ARRAY) is provided in the first cell of the arrayScope array. If the ARRAY type is n-D, then subsequent dimension information is placed in cells 2 to 5 as needed, and provides the beginning and ending bound for each dimension.

The bounds_t structure is defined in sqltypes_td.h as:

typedef struct bounds_t {
   int lowerBound;
   int upperBound;
} bounds_t;

where:

• lowerBound = the lower bound of a dimension.
• upperBound = the upper bound of a dimension.

The array has a size of FNC_ARRAYMAXDIMENSIONS, which is set to the value 5 to indicate that an ARRAY may have a maximum of 5 dimensions.

You should declare the arrayScope array as follows:

bounds_t arrayScope[FNC_ARRAYMAXDIMENSIONS];