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If by first value you mean the one with the minimum date, then:
where t.date = (select min(t2.date) from t t2 where t2.uid = t.uid);
For optimal performance, you want an index on
Selecting first and last values in a group, Similarly, the close value should be the last _close from that week. Is it possible to select something like FIRST() and LAST() in MySql so that the above could be The PARTITION BY clause divides the rows of the result sets into partitions to which the FIRST_VALUE() function applies. If you skip the PARTITION BY clause, the function treats the whole result set as a single partition. order_clause. The order_clause clause sorts the rows in partitions to which the FIRST_VALUE() function applies.
LIMIT, as in:
select * from t order by date limit 1
SQL FIRST() Function, The FIRST() function returns the first value of the selected column. SQL FIRST() Workaround in SQL Server, MySQL and Oracle. SQL Server Syntax. SELECT Returns the first value in an ordered set of values in SQL Server 2019 (15.x). Transact-SQL Syntax Conventions. Syntax FIRST_VALUE ( [scalar_expression ] ) OVER ( [ partition_by_clause ] order_by_clause [ rows_range_clause ] ) Arguments. scalar_expression Is the value to be returned.
with t as
select *, row_number() over (partition by uid order by date) as rn
select * from t
where rn = 1
First() and Last() in mySql, There was one recommendation to use a SELECT and a LIMIT 1 wit the the first and last update time-stamp of records with the same value of The FIRST_VALUE () function is a window function that returns the first value in an ordered partition of a result set. The following shows the syntax of the FIRST_VALUE () function: FIRST_VALUE (scalar_expression) OVER ([PARTITION BY partition_expression, ] ORDER BY sort_expression [ASC | DESC],
Getting the first row of the mysql resource string?, How can I get only the first record in SQL query? SELECT * FROM ( SELECT first_name, LENGTH(first_name) FROM Employees ORDER BY LENGTH(first_name) ASC FETCH FIRST 1 rows ONLY) UNION SELECT * FROM ( SELECT first_name, LENGTH(first_name) FROM Employees ORDER BY LENGTH(first_name) DESC FETCH FIRST 1 rows ONLY) ORDER BY 2 desc; How to select a first row from a MySQL table using just SQL, How can I get first row in MySQL using PHP? You didn't specify how the order is determined, but this will give you a rank value in MySQL: SELECT t.*, @rownum := @rownum +1 AS rank FROM TBL_FOO t JOIN (SELECT @rownum := 0) r WHERE t.name = 'sarmen' Then you can pick out what rows you want, based on the rank value.
MySQL first(), Actually, the result is deterministic iff values in the column col are unique. Otherwise, if there are duplicates, again, any row the has the lowest value existing in co Look, this time everything is numbered 1 and every row is returned. Wonky. This is exactly what the MySQL manual page on user variables warns about. This technique is pretty much non-deterministic, because it relies on things that you and I don’t get to control directly, such as which indexes MySQL decides to use for grouping.
Comments What's the rule you used? Do you mean... by date? Just to confirm, is 23 considered the first value because it has the earliest date? Define "first". Unless you specify an ordering then there's no meaningful concept of "first, second, third, etc." skip date column get from valueid initial @ShubhamSeth: Can you clarify what you mean by that? The language barrier appears to be pretty significant here. skip date column I have no idea what you mean.