When using flattened version of the table, updates to MU and PE fields are accomplished by using the update SQL statement. Simply provide a new value for the column occurrence you want to modify. For example, if a record in the employees table currently has two occurrences in the LANG MU field, and you want to modify the second occurrence, use the following SQL statement (you must know the ISN number of the existing record you want to modify):

When using the rotated and root version of the table, a SQL update is also used to modify the data. The desired occurrence for modification must be specified using the cnxarraycolumn pseudo field. This pseudo field is zero based. So if you want to modify the first occurrence of a MU field, you would specify cnxarraycolumn=0 in the where clause of the update statement. If you want to modify the second occurrence of a MU field, you would specify cnxarraycolumn=1 in the where clause of the update statement.

Using the same example, updating the second occurrence of the LANG MU field would require the following SQL statement.

Updating the SQL count fields that return the number of occurrences in a MU/PE will not cause an error, but any attempts to change the count field directly using an update statement will be ignored.