private ValidationErrors validateSingleColumn(AddColumnStatement statement, Database database) {
ValidationErrors validationErrors = new ValidationErrors();
validationErrors.checkRequiredField("columnName", statement.getColumnName());
validationErrors.checkRequiredField("columnType", statement.getColumnType());
validationErrors.checkRequiredField("tableName", statement.getTableName());
if (statement.isPrimaryKey() && (database instanceof H2Database
|| database instanceof DB2Database
|| database instanceof DerbyDatabase
|| database instanceof SQLiteDatabase)) {