pgtypes.c

关系型数据库 Postgresql 6.5.2

		else
			return maxsize;
	}

	/*	Size is unknown -- handle according to parameter */
	if (QR_get_atttypmod(result, col) > -1)
		return QR_get_atttypmod(result, col);

	if (type == PG_TYPE_BPCHAR || handle_unknown_size_as == UNKNOWNS_AS_LONGEST) {
		p = QR_get_display_size(result, col);
		mylog("getCharPrecision: LONGEST: p = %d\n", p);
	}

	if (p < 0 && handle_unknown_size_as == UNKNOWNS_AS_MAX)
		return maxsize;
	else
		return p;
}

/*	For PG_TYPE_VARCHAR, PG_TYPE_BPCHAR, SQLColumns will 
	override this length with the atttypmod length from pg_attribute .

	If col >= 0, then will attempt to get the info from the result set.
	This is used for functions SQLDescribeCol and SQLColAttributes.
*/
Int4 pgtype_precision(StatementClass *stmt, Int4 type, int col, int handle_unknown_size_as)
{

	switch(type) {

	case PG_TYPE_CHAR:			return 1;
	case PG_TYPE_CHAR2:			return 2;
	case PG_TYPE_CHAR4:			return 4;
	case PG_TYPE_CHAR8:       	return 8;
	case PG_TYPE_CHAR16:       	return 16;

	case PG_TYPE_NAME:			return NAME_FIELD_SIZE;

	case PG_TYPE_INT2:          return 5;

	case PG_TYPE_OID:
	case PG_TYPE_XID:
	case PG_TYPE_INT4:          return 10;

	case PG_TYPE_FLOAT4:        
	case PG_TYPE_MONEY:			return 7;

	case PG_TYPE_FLOAT8:        return 15;

	case PG_TYPE_DATE:			return 10;
	case PG_TYPE_TIME:			return 8;

	case PG_TYPE_ABSTIME:		
	case PG_TYPE_DATETIME:		
	case PG_TYPE_TIMESTAMP:		return 19;

	case PG_TYPE_BOOL:			return 1;

	case PG_TYPE_LO:			return SQL_NO_TOTAL;

	default:

		if (type == stmt->hdbc->lobj_type)	/* hack until permanent type is available */
			return SQL_NO_TOTAL;

		/*	Handle Character types and unknown types */
		return getCharPrecision(stmt, type, col, handle_unknown_size_as);
    }
}

Int4 pgtype_display_size(StatementClass *stmt, Int4 type, int col, int handle_unknown_size_as)
{
	switch(type) {
	case PG_TYPE_INT2:			return 6;

	case PG_TYPE_OID:
	case PG_TYPE_XID:			return 10;

	case PG_TYPE_INT4:			return 11;

	case PG_TYPE_MONEY:			return 15;	/* ($9,999,999.99) */

	case PG_TYPE_FLOAT4:		return 13;

	case PG_TYPE_FLOAT8:		return 22;
	
	/*	Character types use regular precision */
	default:
		return pgtype_precision(stmt, type, col, handle_unknown_size_as);
	}
}

/*	For PG_TYPE_VARCHAR, PG_TYPE_BPCHAR, SQLColumns will 
	override this length with the atttypmod length from pg_attribute 
*/
Int4 pgtype_length(StatementClass *stmt, Int4 type, int col, int handle_unknown_size_as)
{
	switch(type) {

	case PG_TYPE_INT2:          return 2;

	case PG_TYPE_OID:
	case PG_TYPE_XID:
	case PG_TYPE_INT4:          return 4;

	case PG_TYPE_FLOAT4:
	case PG_TYPE_MONEY:			return 4;

	case PG_TYPE_FLOAT8:        return 8;

	case PG_TYPE_DATE:
	case PG_TYPE_TIME:			return 6;

	case PG_TYPE_ABSTIME:		
	case PG_TYPE_DATETIME:
	case PG_TYPE_TIMESTAMP:		return 16;


	/*	Character types use the default precision */
	default:	
		return pgtype_precision(stmt, type, col, handle_unknown_size_as);
    }
}

Int2 pgtype_scale(StatementClass *stmt, Int4 type)
{
	switch(type) {

	case PG_TYPE_INT2:
	case PG_TYPE_OID:
	case PG_TYPE_XID:
	case PG_TYPE_INT4:
	case PG_TYPE_FLOAT4:
	case PG_TYPE_FLOAT8:
	case PG_TYPE_MONEY:
	case PG_TYPE_BOOL:

	/*	Number of digits to the right of the decimal point in "yyyy-mm=dd hh:mm:ss[.f...]" */
	case PG_TYPE_ABSTIME:		
	case PG_TYPE_DATETIME:		
	case PG_TYPE_TIMESTAMP:		return 0;

	default:					return -1;
	}
}


Int2 pgtype_radix(StatementClass *stmt, Int4 type)
{
    switch(type) {
    case PG_TYPE_INT2:
    case PG_TYPE_OID:
    case PG_TYPE_INT4:
    case PG_TYPE_FLOAT4:
	case PG_TYPE_MONEY:
    case PG_TYPE_FLOAT8:        return 10;

    default:                    return -1;
    }
}

Int2 pgtype_nullable(StatementClass *stmt, Int4 type)
{
	return SQL_NULLABLE;	/* everything should be nullable */
}

Int2 pgtype_auto_increment(StatementClass *stmt, Int4 type)
{
	switch(type) {

	case PG_TYPE_INT2:         
	case PG_TYPE_OID:
	case PG_TYPE_XID:
	case PG_TYPE_INT4:         
	case PG_TYPE_FLOAT4:       
	case PG_TYPE_MONEY:
	case PG_TYPE_BOOL:
	case PG_TYPE_FLOAT8:

	case PG_TYPE_DATE:
	case PG_TYPE_TIME:			
	case PG_TYPE_ABSTIME:		
	case PG_TYPE_DATETIME:		
	case PG_TYPE_TIMESTAMP:		return FALSE;

	default:					return -1;
	}    
}

Int2 pgtype_case_sensitive(StatementClass *stmt, Int4 type)
{
    switch(type) {
    case PG_TYPE_CHAR:          

	case PG_TYPE_CHAR2:
	case PG_TYPE_CHAR4:
    case PG_TYPE_CHAR8:         
	case PG_TYPE_CHAR16:		

    case PG_TYPE_VARCHAR:       
    case PG_TYPE_BPCHAR:
    case PG_TYPE_TEXT:
    case PG_TYPE_NAME:          return TRUE;

    default:                    return FALSE;
    }
}

Int2 pgtype_money(StatementClass *stmt, Int4 type)
{
	switch(type) {
	case PG_TYPE_MONEY:			return TRUE;
	default:					return FALSE;
	}    
}

Int2 pgtype_searchable(StatementClass *stmt, Int4 type)
{
	switch(type) {
	case PG_TYPE_CHAR:          
	case PG_TYPE_CHAR2:
	case PG_TYPE_CHAR4:			
	case PG_TYPE_CHAR8:
	case PG_TYPE_CHAR16:		

	case PG_TYPE_VARCHAR:       
	case PG_TYPE_BPCHAR:
	case PG_TYPE_TEXT:
	case PG_TYPE_NAME:          return SQL_SEARCHABLE;

	default:					return SQL_ALL_EXCEPT_LIKE;
	}    
}

Int2 pgtype_unsigned(StatementClass *stmt, Int4 type)
{
	switch(type) {
	case PG_TYPE_OID:
	case PG_TYPE_XID:			return TRUE;

	case PG_TYPE_INT2:
	case PG_TYPE_INT4:
	case PG_TYPE_FLOAT4:
	case PG_TYPE_FLOAT8:
	case PG_TYPE_MONEY:			return FALSE;

	default:					return -1;
	}
}

char *pgtype_literal_prefix(StatementClass *stmt, Int4 type)
{
	switch(type) {

	case PG_TYPE_INT2:
	case PG_TYPE_OID:
	case PG_TYPE_XID:
	case PG_TYPE_INT4:
	case PG_TYPE_FLOAT4:
	case PG_TYPE_FLOAT8:        
	case PG_TYPE_MONEY:			return NULL;

	default:					return "'";
	}
}

char *pgtype_literal_suffix(StatementClass *stmt, Int4 type)
{
	switch(type) {

	case PG_TYPE_INT2:
	case PG_TYPE_OID:
	case PG_TYPE_XID:
	case PG_TYPE_INT4:
	case PG_TYPE_FLOAT4:
	case PG_TYPE_FLOAT8:        
	case PG_TYPE_MONEY:			return NULL;

	default:					return "'";
	}
}

char *pgtype_create_params(StatementClass *stmt, Int4 type)
{
	switch(type) {
	case PG_TYPE_CHAR:
	case PG_TYPE_VARCHAR:		return "max. length";
	default:					return NULL;
	}
}


Int2 sqltype_to_default_ctype(Int2 sqltype)
{
    // from the table on page 623 of ODBC 2.0 Programmer's Reference
    // (Appendix D)
    switch(sqltype) {
    case SQL_CHAR: 
    case SQL_VARCHAR:
    case SQL_LONGVARCHAR:
    case SQL_DECIMAL:
    case SQL_NUMERIC:
    case SQL_BIGINT:
		return SQL_C_CHAR;

    case SQL_BIT:
		return SQL_C_BIT;

    case SQL_TINYINT:
		return SQL_C_STINYINT;

    case SQL_SMALLINT:
		return SQL_C_SSHORT;

    case SQL_INTEGER:
		return SQL_C_SLONG;

    case SQL_REAL:
		return SQL_C_FLOAT;

    case SQL_FLOAT:
    case SQL_DOUBLE:
		return SQL_C_DOUBLE;

    case SQL_BINARY:
    case SQL_VARBINARY:
    case SQL_LONGVARBINARY:
		return SQL_C_BINARY;

    case SQL_DATE:
		return SQL_C_DATE;

    case SQL_TIME:
		return SQL_C_TIME;

    case SQL_TIMESTAMP:
		return SQL_C_TIMESTAMP;

    default:			/* should never happen */
		return SQL_C_CHAR;	
    }
}