How do I count two columns in SQL?

Posted on by Muna Meyer

How do I count two columns in SQL?

5 Answers

  1. count(*) : rows.
  2. count(col1) : rows where col1 is not null.
  3. count(col2) : rows where col2 is not null.
  4. count(distinct col1) : distinct col1 values.
  5. count(distinct col2) : distinct col2 values.
  6. count(distinct col1, col2) : distinct (col1, col2) values combinations.

Can count be used on multiple columns in SQL?

You can GROUP BY multiple columns, to get the count of each combination.

How do I count words in a column in SQL?

Count Word In SQL Server

  1. CREATE FUNCTION [dbo].[fn_WordCount] ( @Param VARCHAR(4000) )
  2. RETURNS INT.
  3. AS.
  4. BEGIN.
  5. DECLARE @Index INT.
  6. DECLARE @Char CHAR(1)
  7. DECLARE @PrevChar CHAR(1)
  8. DECLARE @WordCount INT.

How do I count the number of columns in SQL?

Query to count the number of columns in a table: select count(*) from user_tab_columns where table_name = ‘tablename’; Replace tablename with the name of the table whose total number of columns you want returned.

How do I count repeated words in SQL?

How to Find Duplicate Values in SQL

  1. Using the GROUP BY clause to group all rows by the target column(s) – i.e. the column(s) you want to check for duplicate values on.
  2. Using the COUNT function in the HAVING clause to check if any of the groups have more than 1 entry; those would be the duplicate values.

How do I count words in mysql?

To identify the number of words, we need to count the number of characters in a string and count the characters without the spaces and new lines. When we subtract the two, we get the word count. Let’s look at an example. The query will return the number of words in each content row as wordcount .

How do I count the number of columns in SQL Server?

Here is the SQL query to count the number of columns in Employee table:

  1. SELECT count (column_name) as Number. FROM information_schema.columns. WHERE table_name=’Employee’
  2. SELECT column_name,table_name as Number. FROM information_schema.columns.
  3. SELECT column_name,table_name as Number. FROM information_schema.columns.

Can we use GROUP BY with 2 columns in SQL?

SELECT Statement: The GROUP BY Clause in SQL A GROUP BY clause can contain two or more columns—or, in other words, a grouping can consist of two or more columns.

How to use the count function in SQL?

Introduction to SQL COUNT function 1 By default, the COUNT function uses the ALL keyword whether you specify it or not. The ALL keyword means that all items… 2 If you specify the DISTINCT keyword explicitly, only unique non-null values are considered. The COUNT function returns 4… More

How do I get the number of rows in an SQL table?

SQL COUNT (*) example. To get the number of rows in the employees table, you use the COUNT (*) function table as follows: SELECT COUNT (*) FROM employees; See it in action. To find how many employees who work in the department id 6, you add the WHERE clause to the query as follows: SELECT COUNT (*) FROM employees WHERE department_id = 6;

Is count (distinct COL1) the same as SELECT COUNT (*)?

(Please note also that COUNT(DISTINCT col1, col2)is notthe same as select count(*) from (select distinct col1, col2 from demo) as distinctAll.) – Andriy M Nov 12 ’19 at 20:43 2 Welcome to DBA.SE!

How do you use count in SQL with ORDER BY clause?

SQL COUNT(*) with ORDER BY clause example. You can use the COUNT(*) function in the ORDER BY clause to sort the number of rows per group. For example, the following statement gets the number of employees for each department and sorts the result set based on the number of employees in descending order. COUNT(*) DESC;