Getting row count from a table in mySql

Question

I have a table named 'blogDetails' having blogId, userId, blogTitle, blogContent I have another table named 'blogPopularity' having blogId, userId, popularityStat.

Now in the second table(blogPopularity) the field 'popularityStat' can contains either 'L' (for likes) or 'D' (for dislikes).

I am using Stored Procedure to insert both contents(to blogDetails) and like/dislike status(to blogPopularity).

I want to display the number of Likes and Dislikes for each blog.

Anybody suggest me how to do this.

Answer 1

SELECT  a.blogId, 
        a.blogTitle,
        SUM(CASE WHEN b.popularityStat = 'L' THEN 1 ELSE 0 END) `LIKES`,
        SUM(CASE WHEN b.popularityStat = 'D' THEN 1 ELSE 0 END) `DISLIKES`
FROM    blogDetails a
        LEFT JOIN blogPopularity b
            ON a.blogID = b.blogID
GROUP   BY  a.blogId, a.blogTitle

Sample Result

╔════════╦═══════════╦═══════╦══════════╗
║ BLOGID ║ BLOGTITLE ║ LIKES ║ DISLIKES ║
╠════════╬═══════════╬═══════╬══════════╣
║      1 ║ Title1    ║     7 ║        3 ║
║      2 ║ Title2    ║     6 ║        4 ║
║      3 ║ Title3    ║     3 ║        1 ║
╚════════╩═══════════╩═══════╩══════════╝