OracleDataStore uses the normal JDBCTextFeatureWriter that puts every non geometry value between quotes. Oracle before version 10 accepts '0' for a NUMBER field, but not '0.0'. So any float attribute (or double or whatever) won't be accepted. We should use a specific OracleFeatureWriter instead to not put quotes around numbers or we can modifiy the normal JDBCTextFeatureWriter to distinguish number attributes like this: else if( Number.class.isAssignableFrom(attributeTypes[i].getType()) ) { attrValue = attributes[i] != null ? String.valueOf(attributes[i]) : null; } else { attrValue = addQuotes(attributes[i]); }