Simple statistics
They provide simple statistics on the number of records falling in certain categories including the number of rows, the number of null values, the number of distinct and unique values, the number of duplicates, or the number of blank fields.
- Blank Count: counts the number of blank rows. A "blank" is a non
null textual data that contains only white space. Note that Oracle does not
distinguish between the empty string and the null value.
The LONG VARCHAR data type in Vertica is not supported.
- Default Value Count: counts the number of default values.
- Distinct Count: counts the number of distinct values of your column.
- Duplicate Count: counts the number of values appearing more than once. You have the relation: Duplicate count + Unique count = Distinct count. For example, a,a,a,a,b,b,c,d,e => 9 values, 5 distinct values, 3 unique values, 2 duplicate values.
- Null Count: counts the number of null rows.
- Row Count: counts the number of rows.
- Unique Count: counts the number of distinct values with only one occurrence. It is necessarily less or equal to Distinct counts.
The following table shows the indicators that you can select in any database:
Indicator | Supported data types with the Java analysis engine | Supported data types with the SQL analysis engine |
---|---|---|
Row Count | All data types | All data types |
Null Count | All data types | All data types |
Distinct Count | All data types | All data types |
Unique Count | All data types | All data types |
Duplicate Count | All data types | All data types |
Blank Count | Text | Text |
Default Value Count | All data types, but only when the database table has a default value constraint | All data types, but only when the database table has a default value constraint |