Varying-length rows with nulls for edit and validation routines

A varying-length column can allow null values. In basic row format, the value in the length field includes the length of the null indicator byte but does not include the length field itself.

Begin program-specific programming interface information.

The following table shows how the row would look in storage if nulls were allowed in DEPTNAME. The first value in the DEPTNAME column indicates the column length as a hexadecimal value.

Table 1. A varying-length row in basic row format in the sample department table
DEPTNO	DEPTNAME		MGRNO		ADMRDEPT	LOCATION
C01	0013	Information center	00	000030	A00	00	New York

An empty string has a length of one, a X'00' null indicator, and no data following.

In reordered row format, if a table has any varying-length columns, with or without nulls, all fixed length columns are placed at the beginning of the row, followed by the offsets to the varying length columns, followed by the values of the varying length columns. End program-specific programming interface information.