comparision of two columns within a single table

i have a table开发者_开发知识库 alpha ,this contains two columns A And B. I need to find out how many A's are there for B.

      A             B   
      1     1
      2     2
      3     3
      4     3
      5     4
      6     7

Try grouping :

SELECT `B`, COUNT(*) AS `Count`
FROM `Alpha` 
GROUP BY `B`

try this

SELECT COUNT( * ) AS  `Items` ,  `B` 
FROM  `alpha` 
GROUP BY  `b`