Hibernate 2.1.x, MySQL alter table add column DDL

fivesticks · **Posted:** Tue Feb 17, 2004 7:18 pm

Hello,

First, as always: Kudos to Hibernate team. Thanks for great project.

I've experienced a problem with a few versions of Hibernate 2.1.x. When adding a boolean field to a MySQL table with a not-null value set to true, the ddl comes out as:

alter table tablename add column booleancolumn BIT

leaving off the "NOT NULL"

Finally motivated to go a little deeper, I went into the src for the Table class and changed some code to include this. My question is: is this likely to cause any negative effects that aren't immediately obvious? I'm not too concerned about database independence for this particular product.

Thanks in advance.

Reid

code is from net.st.hibernate.mapping.Table.sqlAlterStrings v 2.1.2

Code:

         if (columnInfo==null) {
            // the column doesnt exist at all.
            StringBuffer alter = new StringBuffer( root.toString() )
               .append(' ')
               .append( col.getQuotedName(dialect) )
               .append(' ')
               .append( col.getSqlType(dialect, p) );
            if ( col.isUnique() && dialect.supportsUnique() ) {
               alter.append(" unique");
            }
// I added from here...
            if ( !col.isNullable()) {
               alter.append(" NOT NULL ");
            }
//...to here
            if ( col.hasCheckConstraint() ) {
               alter.append(" check(")
                  .append( col.getCheckConstraint() )
                  .append(")");
            }
            results.add( alter.toString() );
            

         }

gavin · **Posted:** Tue Feb 17, 2004 7:38 pm

It is usually necessary to specify a default value when adding a column....

fivesticks · **Posted:** Tue Feb 17, 2004 8:00 pm

Hello,

Yes. However, in this particular case, MySQL does a nice job of saying if its a BIT, and null is not allowed, then default it to zero. At the very least, then, I should take that into the Dialect area? Not sure I'm ready for that tonight. ;-)

Just looking through the docs and DTD I don't see a setting that allows me to set a default there. Am I missing it?

Cheers,

Reid