After the data source is opened and accessed, let~{!/~}s move on to look at how to further compute data with a series offilter,sort,group
l Problem In a restaurant capable of holding 1,000 people, the seats are numbered in order and recorded in a database tmerge,file,import,group,count,select
l Problem All records about the sales contracts of an enterprise are listed as below: The lost clients in a year are thchurn rate,file,import,group,len
Here’s how to use enum() function.enumeration,group
Here’s how to use group() function.group
Here’s how to use groupn() function.group