I understand that you are trying to insert a black space into an SQL table using the "datainsert" function.
The "datainsert" function automatically casts the string '' which is of type MATLAB 'char' to NULL prior to the insertion. One workaround for this issue is to use the string representation in Java as shown in the following example:
Suppose I have a MYSQL table called "names" with three fields 'id', 'name' and 'subject'. I want to insert a record with the 'name' column's value to be '' (the empty string), I would do the following:
>> colnames = {'id','name' , 'subject'};
>> data = {13, java.lang.String(''),'asd'};
>> datainsert(conn,tablenames,colnames,data)
Hope I have answered your question.
