how to select unique in sql code example
Example 1: MySQL DISTINCT
When querying data from a table, you may get duplicate rows. In order to remove these duplicate rows, you use the DISTINCT clause in the SELECT statement.
Here is the syntax of the DISTINCT clause:
SELECT DISTINCT
select_list
FROM
table_name;
Example 2: query DISTINCT
SELECT DISTINCT Column_name FROM table_name;
Example 3: unique element in sql
DISTINCT
- select distinct * from employees; ==> retrieves any row if it has at
least a single unique column.
- select distinct first_name from employees; ==> retrieves unique names
from table. (removes duplicates)
- select distinct count(*) from employees; retrieve number of unique rows
if any row has at least a single unique data.