根据表1上的每个ID连接2个表

Question

Let's say.. I have 2 table like this

Table 1

Table 2

I want to join 2 table above. Display each content from column name_tb1 on Table 1 and get the output of total/num rows from name_tb2 on Table 2 based from each of id_tb1

Example Output:

First (3 Row)
Second (2 Row)
Third (3 Row)

Answer 1

This should do the trick.

SELECT
    table_1.id_tb1, 
    count(*) 
FROM
    table_1, 
    table_2 
WHERE 
    table_1.id_tb1 = table_2.id_tb1 
GROUP BY 
    table_1.id_tb1

ON a sidenote, not thrilled by your naming convention and image. We like to help but copy and paste makes all easier. From a image we can't copy/paste text.

For naming call the PRI-KEY of a table 'id', and prefix the foreign key with the table name.

SO:

• table1.id
• table1.name
• table2.id
• table2.table1_id
• table2.name