Programming Interfaces Guide
   CHAPTER 5. The Open Client Interface     

Data type mappings

Open Client has its own internal data types, which differ in some details from those available in Adaptive Server Anywhere. For this reason, Adaptive Server Anywhere internally maps some data types between those used by Open Client applications and those available in Adaptive Server Anywhere.

  Data type mapping between Open Client and Adaptive Server Anywhere

The following table illustrates the mapping of data types performed by Adaptive Server Anywhere between internal Adaptive Server Anywhere data types and Open Client data types.

The base data type column is for information only. Applications receive the data type information as in the ASA data type column. The base data type is hidden from the Open Client application.

Open Client data type	ASA data type	ASA base data type
binary (x)	binary (x)
bit	bit
char	char
datetime	datetime	timestamp
smalldatetime	smalldatetime	timestamp
decimal	decimal
numeric	numeric
real	real
float	double
image	long binary
tinyint	tinyint
smallint	smallint
int	int
bigint	bigint
money	money	decimal (19,4)
smallmoney	smallmoney	decimal (10,4)
text	long varchar
varchar	varchar
varbinary	varbinary
timestamp	timestamp
All others	Error

  Mapping of Adaptive Server Anywhere data types

The following table lists the mappings of data types supported in Adaptive Server Anywhere that have no direct counterpart in Open Client.

ASA data type	Open Client data type
unsigned short	smallint
unsigned int	int
unsigned bigint	bigint
date	smalldatetime
time	smalldatetime
serialization	longbinary
java	longbinary
string	varchar
timestamp struct	datetime

  Range limitations in data type mapping

Some data types have different ranges in Adaptive Server Anywhere than in Open Client. In such cases, overflow errors can occur during retrieval or insertion of data.

The following table lists Open Client application data types that can be mapped to Adaptive Server Anywhere data types, but with some restriction in the range of possible values.

In most cases, the Open Client data type is mapped to a Adaptive Server Anywhere data type that has a greater range of possible values. As a result, it is possible to pass a value to Adaptive Server Anywhere that will be accepted and stored in a database, but one that is too large to be fetched by an Open Client application.

Data type	Implementation	Lower range	Upper range
MONEY	Open Client	-922,337,203 ,685,477.5808	922,337,203 ,685,477.5807
MONEY	Adaptive Server Anywhere	-1e15 + 0.0001	1e15 - 0.0001
SMALLMONEY	Open Client	-214,748.3648	214,748.3647
DECIMAL (10,4)	Adaptive Server Anywhere	-1e6 + 0.0001	1e6 - 0.0001
TIMESTAMP	Open Client	N/A	N/A
DATETIME	Open Client	Jan 1, 1753	Dec 31, 9999
SMALLDATETIME	Open Client	Jan 1, 1900	June 6, 2079
DATETIME	Adaptive Server Anywhere	Jan 1, 0001	Dec 31, 9999
BIT	Open Client	0	1
TINYINT	Adaptive Server Anywhere	0	255

Example 

For example, the Open Client MONEY and SMALLMONEY data types do not span the entire numeric range of their underlying Adaptive Server Anywhere implementations. Therefore it is possible to have a value in a Adaptive Server Anywhere column which exceeds the boundaries of the Open Client data type MONEY. When the client fetches any such offending values via Adaptive Server Anywhere, an error is generated (Error 22: Invalid data format. Possible overflow or underflow).

Timestamps 

The Adaptive Server Anywhere implementation of the Open Client TIMESTAMP data type, when such a value is passed in Adaptive Server Anywhere is different from that of Adaptive Server Enterprise. In Adaptive Server Anywhere the value is mapped to the Adaptive Server Anywhere DATETIME data type. The default value is NULL in Adaptive Server Anywhere, and no guarantee is made of its uniqueness. By contrast, Adaptive Server Enterprise ensures that the value is monotonically increasing in value, and so is unique.

By contrast, the Adaptive Server Anywhere TIMESTAMP data type contains year, month, day, hour, minute, second and fraction of second information, and the DATETIME data type has a greater range of possible values than the Open Client data types that are mapped to it by Adaptive Server Anywhere.

Other restrictions 

Adaptive Server Adaptive Server Anywhere defines SYSNAME as VARCHAR (30) and does not allow the Open Server client application to specify the length of the data field.

  Data types with limited compatibility

The following tables lists Open Client data types for which there is nosupport in Adaptive Server Anywhere.

Open Client application data type	Problem
LONG	Not supported
SENSITIVITY	Not supported
BOUNDARY	Not supported
VOID	Not supported