外部数据类型的数据类型代码如下表所示。

YashanDB外部数据类型代码	绑定、定义支持情况（B in/B out/D 表示bind input/bind output/define）	对应C数据结构
SQLT_INT	B in/D	signed char signed short signed int signed long long
SQLT_STR	B in/D	char[n+1]
SQLT_AFC	B in/D	char[n]
SQLT_CHR	D	char[n]
SQLT_LNG	B in/D	char[n]
SQLT_FLT	B in/D	float double
SQLT_TIMESTAMP	B in/D	OCIDateTime *
SQLT_INTERVAL_DS	B in/D	OCIInterval *
SQLT_VNU	B in	char[22]
SQLT_BDOUBLE	B in	double
SQLT_BLOB	B in/D	OCILobLocator*
SQLT_CLOB	B in/D	OCILobLocator*
SQLT_RSET	B out/D	OCIStmt*