I have this table using InnoDB as engine: create table if not exists Playlists( UserId bigint unsigned not null, Title varchar(50) not null, IsPublic bool not null, primary key (UserId, Title), foreign key (UserId) references Users(Id) on delete cascade on…
I can simply use LAG() to calculate the percentage change from my table (see below) of this month compared to the data 3 months ago or 1 year ago. But now, I want to get this result: calculate the sum…
Here is the query, here al.activated_date column is having timestamp. I want to group by application.id, application_logs.activated date. When i remove DATE(al.activated_date), query excution time is 1.2sec. But when i use it, exceeds 15sec.. SELECT a.id, a.description, DATE(al.activated_date) as activated_date,…
I have the following table: CREATE TABLE `ages` ( `id` tinyint(3) UNSIGNED NOT NULL, `min_age` decimal(4,2) NOT NULL, `max_age` decimal(4,2) NOT NULL ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci; With the following data: INSERT INTO `ages` (`id`, `min_age`, `max_age`) VALUES (1, 4.00,…
I expect the SQL-Statement to update a limited amounts of rows, instead of every row: UPDATE Join_Test_1 SET ANumber = 3 FROM Join_Test_1 AS ST1 INNER JOIN Join_Test_2 AS ST2 ON ST1.PKID = ST2.PKID; I expect the statement to behave…
This is my database design: CREATE TABLE post ( id INT, user_id INT, type_id INT ); I want to get a list of users who wrote posts of types 1 and 2 only. This seems to be working: select distinct…
I have a report where all the dates should be displayed in the client's time zone. The report includes a feature that allows exporting to Excel. For both generating the report and exporting it to Excel, I am using the…
I checked the behavior of SQL when we want to have values mapped immediately from an Entity to a DTO object, for example. If I gave an example in the constructor: SELECT new Test(T) FROM Test T I saw 2…
I want to create a SQL stored procedure that checks passwords at login. This should be a very common question however I could not find an answer anywhere to my specific question, which is about data types, or perhaps something…
I'm using python with redshift_connector, and analysing the data with pandas. When accessing a redshift db with selecting n columns, I got i lines. However when I wanted to add a new column to this query, it timed out after…