SQLite – DISTINCT Keyword
SQLite DISTINCT keyword is used in conjunction with SELECT statement to eliminate all the duplicate records and fetching only the unique records.
There may be a situation when you have multiple duplicate records in a table. While fetching such records, it makes more sense to fetch only unique records instead of fetching duplicate records.
Syntax
Following is the basic syntax of DISTINCT keyword to eliminate duplicate records.
SELECT DISTINCT column1, column2,.....columnN FROM table_name WHERE [condition]
Example
Consider COMPANY table with 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 see how the following SELECT query returns duplicate salary records.
sqlite> SELECT name FROM COMPANY;
This will produce the following result.
NAME ---------- Paul Allen Teddy Mark David Kim James Paul James James
Now, let us use DISTINCT keyword with the above SELECT query and see the result.
sqlite> SELECT DISTINCT name FROM COMPANY;
This will produce the following result, where there is no duplicate entry.
NAME ---------- Paul Allen Teddy Mark David Kim James