Unique in sql server

Sql unique rows

SELECT
DISTINCT country
FROM City;

Source: learnsql.com

Unique in sql server

CREATE TABLE Persons (
    ID int NOT NULL UNIQUE,
    LastName varchar(255) NOT NULL,
    FirstName varchar(255),
    Age int
);

How to select 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.

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.

Sql unique select

SELECT DISTINCT col1, col2, ....
FROM table_name;

SELECT col1, MIN(col2)
FROM table_name
GROUP BY col1;

Similar codes

2 votes192 views1 answer
Mysql time ago difference
SQL
0 vote177 views1 answer
Mysql concat and use as where column
SQL
0 vote174 views1 answer
SQL COMO ALTERA NOME DE TABELA
SQL
0 vote185 views1 answer
Select place default lat long
SQL
1 vote188 views2 answers
Get table column names sql laravel
SQL
0 vote335 views1 answer
Mysql delete entire row on condition
SQL
-1 vote135 views1 answer
Oracle db list usernames
SQL
5 votes171 views1 answer
Postgres integer to serial
SQL
-1 vote234 views1 answer
Sql show custom constraints
SQL
0 vote180 views1 answer
Array aggre distinct postgres
SQL