16-bit signed integer  

short int i; unsigned short int i;

32-bit signed integer  

long int l; unsigned long int l;

4-byte floating point number  

float f;

8-byte floating point number  

double d;

Packed decimal number  

DECL_DECIMAL(p,s) typedef struct TYPE_DECIMAL { char array[1]; } TYPE_DECIMAL;

Null terminated, blank-padded character string  

char a[n]; /* n > 1 */ char *a; /* n = 2049 */

Because the C-language array must also hold the NULL terminator, a char a[n] data type maps to a CHAR(n - 1) SQL data type, which can hold n-1 characters.

NULL terminated UNICODE or wide character string   Each character occupies two bytes of space and so may contain UNICODE characters.

WCHAR a[n]; /* n > 1 */

NULL terminated system-dependent character string   A TCHAR is equivalent to a WCHAR for systems that use UNICODE (for example, Windows Mobile) for their character set; otherwise, a TCHAR is equivalent to a char. The TCHAR data type is designed to support character strings in either kind of system automatically.

TCHAR a[n]; /* n > 1 */

Fixed-length blank padded character string  

char a; /* n = 1 */ DECL_FIXCHAR(n) a; /* n >= 1 */

Variable-length character string with a two-byte length field   When supplying information to the database server, you must set the length field. When fetching information from the database server, the server sets the length field (not padded).

DECL_VARCHAR(n) a; /* n >= 1 */ typedef struct VARCHAR { unsigned short int len; TCHAR array[1]; } VARCHAR;

Variable-length binary data with a two-byte length field   When supplying information to the database server, you must set the length field. When fetching information from the database server, the server sets the length field.

DECL_BINARY(n) a; /* n >= 1 */ typedef struct BINARY { unsigned short int len; unsigned char array[1]; } BINARY;

SQLDATETIME structure with fields for each part of a timestamp  

DECL_DATETIME a; typedef struct SQLDATETIME { unsigned short year; /* for example: 1999 */ unsigned char month; /* 0-11 */ unsigned char day_of_week; /* 0-6, 0 = Sunday */ unsigned short day_of_year; /* 0-365 */ unsigned char day; /* 1-31 */ unsigned char hour; /* 0-23 */ unsigned char minute; /* 0-59 */ unsigned char second; /* 0-59 */ unsigned long microsecond; /* 0-999999 */ } SQLDATETIME;

The SQLDATETIME structure is used to retrieve fields of the DATE, TIME, and TIMESTAMP type (or anything that can be converted to one of these). Often, applications have their own formats and date manipulation code. Fetching data in this structure makes it easier for the programmer to manipulate this data. Note that DATE, TIME, and TIMESTAMP fields can also be fetched and updated with any character type.

If you use a SQLDATETIME structure to enter a date, time, or timestamp into the database, the day_of_year and day_of_week members are ignored.

For more information about the date_format, time_format, timestamp_format, and date_order database options, see Database options.

DT_LONGVARCHAR   Long varying length character data. The macro defines a structure, as follows:

#define DECL_LONGVARCHAR( size ) \ struct { a_sql_uint32 array_len; \ a_sql_uint32 stored_len; \ a_sql_uint32 untrunc_len; \ char array[size+1];\ }

The DECL_LONGVARCHAR struct may be used with more than 32KB of data. Data may be fetched all at once, or in pieces using the GET DATA statement. Data may be supplied to the server all at once, or in pieces by appending to a database variable using the SET statement. The data is not null terminated.

typedef struct BINARY {
  unsigned short int len;
  char array[1];
} BINARY;

DT_LONGBINARY   Long binary data. The macro defines a structure, as follows:

#define DECL_LONGBINARY( size ) \ struct { a_sql_uint32 array_len; \ a_sql_uint32 stored_len; \ a_sql_uint32 untrunc_len; \ char array[size]; \ }

The DECL_LONGBINARY struct may be used with more than 32KB of data. Data may be fetched all at once, or in pieces using the GET DATA statement. Data may be supplied to the server all at once, or in pieces by appending to a database variable using the SET statement.