What's New

Data Types

The following data types are available with DB2 Universal Database Version 5.2 and can be used with the call level interface (CLI):

• "BIGINT"
• "DATALINK"
• "Defined Types"

BIGINT

The following tables are updated in the CLI Guide and Reference as a result of the added support for the BIGINT data type. See the SQL Reference for more information on this new data type.

Table 3, "SQL Symbolic and Default Data Types":

• SQL Data Type: BIGINT
• Symbolic SQL Data Type: SQL_BIGINT
• Default Symbolic C Data Type: SQL_C_BIGINT

Table 4, "C Data Types":

• C Symbolic Data Type: SQL_C_BIGINT
• C Type: SQLBIGINT
• Base C Type: long int (or __int64)

Table 22, "SQLBindParameter Arguments", under SQLBindParameter():

• Add SQL_C_BIGINT to the row for argument "ValueType".
• Add SQL_BIGINT to the row for argument "ParameterType".

Table 116, "SQLGetTypeInfo Arguments, under SQLGetTypeInfo():

Add SQL_BIGINT to the list of supported types for argument "DataType".

DATALINK

The following additions apply to Chapter 2. Writing a DB2 CLI Application of the CLI Guide and Reference as a result of support for the new DATALINK data type.

Three tables require an extra row each:

Table 3. SQL Symbolic and Default Data Types

• SQL Data Type field: DATALINK
• Symbolic SQL Data Type field: SQL_DATALINK
• Default Symbolic C Data Type: SQL_C_DATALINK

Table 4. C Data Types

• C Symbolic Data Type field: SQL_C_DATALINK
• C Type field: SQLCHAR
• Base C type field: unsigned char

Table 7. Supported Data Conversions

The SQL Data Type SQLDATALINK only converts with SQL_C_DATALINK.

Defined Types

The following section is added to Chapter 3. Using Advanced Features.

Using Reference Types

In addition to the distinct types, user defined structured types can also be defined and used as the type for a table or view. Tables or views that are defined using a structured type are called typed tables or typed views. Structured types can be defined in a hierarchy with subtypes and supertypes. These structured types are created using the CREATE TYPE statement. Rows of a typed table or view are identified with an object identifier (OID) that is a reference type. A reference type is defined to have a target type, which must be a structured type. When the root structured type (the structured type without a supertype) is defined, the representation type for the reference type is defined as based on a built-in data type. Similar to user defined types (UDTs), a reference type shares its internal representation with an existing type, but is considered to be a separate and incompatible type for most operations.

Reference types provide a means of referring to rows in typed tables or typed views. Applications continue to work with C data types for application variables, and only need to consider the reference types when constructing C statements.

This means:

• All SQL to C data type conversion rules that apply to the reference type's underlying SQL built-in type apply to the reference type.

• The reference type will have the same default C Type as the underlying SQL built-in type.

• SQLDescribeCol() will return the representation (built-in) type information. The target type name can be obtained by calling SQLColAttribute() with the input descriptor type set to SQL_DESC_REFERENCE_TYPE.

• SQL predicates that involve parameter markers must be explicitly cast to the reference type. This is required since the application can only deal with the built-in types, so before any operation can be performed using the parameter, it must be cast from the C built-in type to the reference type; otherwise an error will occur when the statement is prepared.

For complete rules and a description of reference types refer to the SQL Reference.

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