SQL statement intersetct, minus, Union, Union all summary

The operations of intersect and minus are basically the same as those of Union. Here we will summarize the following:

 

Union: Perform Union operations on two result sets, excluding duplicate rows, and sort the default rules at the same time;

 

Union all: Perform Union operations on the two result sets, including duplicate rows without sorting;

 

Intersect: intersection of two result sets, excluding duplicate rows, and sorting by default rules;

 

Minus performs the Difference Operation on two result sets, excluding duplicate rows and sorting by default rules. (Only the content in the first SQL statement is displayed. If the content in the first SQL statement is in the second SQL statement, it is removed. If it is not in the second SQL statement, it is displayed)

 

You can specify the order by clause in the last result set to change the sorting method.