Count sql

Sql count

/*COUNT(column_name) will return the number of rows from the column 
that are not NULL*/
SELECT COUNT(column_name)
FROM table_name;

/*COUNT(*) will return the number of rows from the table*/
SELECT COUNT(*)
FROM table_name;

Sql join

-- Rows with ID existing in both a, b and c
-- JOIN is equivalent to INNER JOIN
SELECT a.ID, a.NAME, b.VALUE1, c.VALUE1 FROM table1 a 
  JOIN table2 b ON a.ID = b.ID
  JOIN table3 c ON a.ID = c.ID
WHERE a.ID >= 1000;
-- ⇓ Test it ⇓ (Fiddle source link)

Source: sqlfiddle.com

Count sql

SELECT COUNT(column_name)
FROM table_name
WHERE condition;

Counting in sql

SELECT COUNT(*) FROM EMPLOYEES;

Similar codes

0 vote101 views1 answer
Mysql query to check record exists in database table or not
SQL
1 vote109 views2 answers
Sql left characters
SQL
1 vote97 views1 answer
Postgres check blocking
SQL
2 votes105 views1 answer
Set column to not null mysql
SQL
1 vote101 views2 answers
How to check username in mysql command line
SQL
0 vote110 views1 answer
How to add timestamp column in mysql
SQL
0 vote95 views1 answer
Using GROUP BY in MySQL Join Table
SQL
0 vote108 views1 answer
Query only first letter string
SQL
1 vote123 views2 answers
Drop table with constraints
SQL
0 vote129 views1 answer
Local pg_sql to heroku pg_sql
SQL