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How to get distinct rows from a LEFT OUTER JOIN stack?
But since Table1 is my main table the relationship is virtually like a one to many. My app generates a sql which basically gives a result set containing rows from all these tables. The select clause and joins dont change whereas the where clause is generated based on user interaction.
How to join multiple joins yet return distinct values?
What about something like this which doesn’t use explicit JOIN s: If you preface your query with SELECT DISTINCT, you should return only the distinct rows. If I’m understanding the question correctly, you’ll want to use the GROUP BY clause
How to do left join without duplicate rows from left table?
The OUTER APPLY selects a single row (or none) that matches each row from the left table. The GROUP BY performs the entire join, but then collapses the final result rows on the provided columns.
How to select the first row in a group?
If you’re using PostgreSQL you can use DISTINCT ON to find the first row in a group. SELECT customer.*, purchase.* FROM customer JOIN ( SELECT DISTINCT ON (customer_id) * FROM purchase ORDER BY customer_id, date DESC ) purchase ON purchase.customer_id = customer.id
How to get distinct values from two tables?
The trick would be to get the distinct values from both tables, something like this: SELECT a.Code, b.code FROM (–Get the DISTICT Codes from all sets SELECT Distinct Code from Table1 UNION SELECT Distinct Code from Table2) x Left JOIN Table1 a ON x.code = a.Code LEFT JOIN Table2 b ON x.code = b.Code
How is distinct applied in a join query?
The join looks strange but it’s hard to tell without knowing what the tables and their key’s look like. Your DISTINCT is applied to ALL columns in your SELECT statement, not just the one you put it next to in your query. Your DISTINCT and GROUP BY are, at the moment, doing the same exact thing.
When to use distinct and group by in SQL Server?
The join looks strange but it’s hard to tell without knowing what the tables and their key’s look like. Your DISTINCT is applied to ALL columns in your SELECT statement, not just the one you put it next to in your query. Your DISTINCT and GROUP BY are, at the moment, doing the same exact thing. In that specific order.
How to avoid duplicate rows in a multiple table join?
In short, instead of 6 rows it should only show 3 rows. IMP : There might be a delay in posting replies due to time difference (GMT +2:00) and Friday’s Holiday instead of Sunday. If you are pulling data from the three tables, there is no way you can get just three rows if the combinations are different.
How to get one result row per row in Table 1?
To get one result row per row in table 1, you have to use a grouping function on the other tables. For example, if you want the last (in ascending sort order) name and date, you’d use What about something like this which doesn’t use explicit JOIN s: