💻Think like SQL Engine🔥Mastering MS SQL (SubQuery✅)
Intuition\nThis SQL query is selecting the product ID, first year, quantity, and price for all products in the Sales table. It is doing this by joining the Sale
# Intuition\nThis SQL query is selecting the product ID, first year, quantity, and price for all products in the Sales table. It is doing this by joining the Sales table with itself, using the min(year) subquery to identify the first year for each product ID. The inner join clause ensures that only records that match between the two tables are included in the result set.\n\n# Approach\n1. The select clause specifies the columns that you want to select from the table. In this case, you are selecting the product_id, year, quantity, and price.\n\n2. The from clause specifies the table that you want to select from. In this case, you are selecting from the Sales table, aliased as s1.\n\n3. The inner join clause joins the Sales table with itself, aliased as s2. The join condition is that the product_id in s1 must match the product_id in s2, and the year in s1 must match the min_year in s2.\n\n4. The min(year) subquery is used to identify the first year for each product ID. This subquery selects the product_id and the min(year) from the Sales table, and then groups the results by product_id.\n\n5. The and operator is used to combine the two join conditions. This ensures that only records that match both conditions are included in the result set.\n\n# Code\n```\n# Write your MySQL query statement below\nselect \n  s1.product_id, \n  year as first_year, \n  quantity, \n  price \nfrom \n  Sales s1 \n  inner join (\n    select \n      product_id, \n      min(year) min_year \n    from \n      Sales \n    group by \n      product_id\n  ) s2 on s1.product_id = s2.product_id \n  and s2.min_year = s1.year\n```
['MySQL']