SQLite Distinct Categories
SQLite SELECT statement with theDISTINCT keyword used together to eliminate all duplicate records, and only get a unique one-time recording.
There may be a case, there are multiple duplicate records in a table. When extracting such a record, DISTINCT keyword is especially meaningful only get a unique one-time recording, instead of getting duplicate records.
grammar
The basic syntax for the DISTINCT keyword to eliminate duplicate records as follows:
SELECT DISTINCT column1, column2, ..... columnN FROM table_name WHERE [condition]
Examples
Suppose COMPANY table has the following records:
ID NAME AGE ADDRESS SALARY ---------- ---------- ---------- ---------- ---------- 1 Paul 32 California 20000.0 2 Allen 25 Texas 15000.0 3 Teddy 23 Norway 20000.0 4 Mark 25 Rich-Mond 65000.0 5 David 27 Texas 85000.0 6 Kim 22 South-Hall 45000.0 7 James 24 Houston 10000.0 8 Paul 24 Houston 20000.0 9 James 44 Norway 5000.0 10 James 45 Texas 5000.0
First, let us look at the following SELECT query, it returns duplicate payroll records:
sqlite> SELECT name FROM COMPANY;
This produces the following results:
NAME ---------- Paul Allen Teddy Mark David Kim James Paul James James
Now, let's use theDISTINCT keyword in the above SELECT query:
sqlite> SELECT DISTINCT name FROM COMPANY;
This produces the following result, there is no duplicate entries:
NAME ---------- Paul Allen Teddy Mark David Kim James