The comparison may be performed:
Data Selector (Source)
- The target uri may be not given as argument. If this is the case, the comparison will except an empty target.
The report-level argument defines what the command will return:
- resource - a comparison report will be created for all comparison
- record - a comparison report will be created for each comparison and the record data comparison will be available
- all - all type of comparison report will be created
The data-source defines the origin of the data to compare.
- content - the default - the data to compare will be the records
- structure - the data to compare will be the column definitions.
Unique Columns / Driver Columns
The unique columns (driver columns) are the columns that drives the comparison process.
For instance, if you compare two resources that have an unique id column,
- if the comparison has fetched:
- a source record with a id value of 1
- a target record with a id value of 2
- the comparator will:
- mark the source record has missing in the target
- fetch records only from the source until it finds the record with the id 2 or above.