Add more explanation.
@@ -83,6 +83,8 @@ Suppose that `file1.tsv` contains the following table in KGTK format:
| steve | zipcode | 45601 | work | |
+Count the unique values in the `location` column:
+
```bash
kgtk unique -i file1.tsv --column location
@@ -93,6 +95,9 @@ kgtk unique -i file1.tsv --column location
| home | count | 2 |
| work | count | 3 |
+Count the unique values in the `location` column, using
+the value `NONE` for empty values:
+
```bash
kgtk unique -i file1.tsv --column location --empty NONE
@@ -104,6 +109,10 @@ kgtk unique -i file1.tsv --column location --empty NONE
| home | count | 2 |
| work | count | 3 |
+Count the unique values in the `location` column, using
+the value `NONE` for empty values, but use the `node` format
+for the output file:
+
```bash
kgtk unique -i file1.tsv --column location --empty NONE --format node
@@ -113,6 +122,8 @@ kgtk unique -i file1.tsv --column location --empty NONE --format node
| -------- | ---- | ---- | ---- |
| location | 3 | 2 | 3 |
+Give each column name a prefix:
+
```bash
kgtk unique -i file1.tsv --column location --empty NONE --format node --prefix 'location;'
@@ -122,6 +133,8 @@ kgtk unique -i file1.tsv --column location --empty NONE --format node --prefix '
| -------- | ---- | ---- | ---- |
| location | 3 | 2 | 3 |
+Filter the input file and create an edge-stype output file:
+
```bash
kgtk unique -i file1.tsv --column location --where node1 --in peter
```
