I did some experiments for finding empty fields, But i want to know whether there is any other better method. Have to reduce hard disk space.
Method 1: Add "NULL String" in empty fields We can search with null string for empty column & non empty column Observations: - Index size will grow. - Suppose if we add one new column, then old documents will not have null string for that new column in index. - While fetching results, more IO will happen because of null string. Method 2: Add one extra field namely NON_EMPTY_COLUMN and add all not empty column names in that. We can search like NON_EMPTY_COLUMN:Field_Name, for empty column documents we have to search with Not of field name Observations: - Again Index size will grow - Fetching is not costly Method 3: While Searching, iterate through results and check for empty column by using doc.get Observations: - Iterations will become costly, suppose required results is not present in first set of results. - Also IO big impact in this.
