select unique rows in mysql code example

Example 1: mysql remove unique constraint

ALTER TABLE tbl_name DROP INDEX index_name

Example 2: select count of distinct values sql

SELECT COUNT (DISTINCT column-name)  FROM table-name

Example 3: mysql query unique column

SELECT DISTINCT(column_name) FROM your_table_name;

#You can select distinct values for one or more columns. The column names has to be separated with comma.
SELECT DISTINCT column_name_1, column_name_2 FROM your_table_name;

Example 4: mysql set field unique

ALTER TABLE mytbl ADD UNIQUE (columnName);

Example 5: 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 6: query DISTINCT

SELECT DISTINCT Column_name FROM table_name;