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Tag: sql

Find Latest Child Record (With Conditions) Per Parent Record

I have 2 tables with a parent/child hierarchy and am trying to pull the ID for the latest child record for each parent record, but also with conditions applied on the child record that is being pulled. Here’s what my tables look like: Now, let’s say I want to pull ID of latest QuizAttempt for each…

Power BI Report Builder Indicator Formula

I am adding in an indicator to a PBI Report Builder Report. The indicator is based off multiple fields from the dataset so I need to use a formula, to create the three up/down/side arrows. Previously in Crystal Reports this could be implemented using a series of IF statements as follows. The below example is …

Unknown column ‘r’ in field list

I’ve been working on a SQL query for a project, and I face an error message when I want to use it. Here is the query itself : MySQL answers me “Unknown column ‘r’ in field list”. But I dont really understand why I get an error here as I define r in my INNER JOIN. I’m kinda …

Select last value in each group

In database I have two table. I want to join two tables and get last row each SensorType Sensors table: Id CodeNumber PortNumber SensorType IsActive 13 Dht11 3 0 1 14 Dht11 3 2 1 17 Global 100 4 1 18 Dht11 3 1 1 19 Dht11 3 3 1 SensorsValue table (SensorId is foreign key Sensors table): Id SensorId

Oracle SQL hierarchical query from bottom to top

I have a table where I want to go from bottom to top using hierarchical queries. The problem is that I need the get the value of one column from root (top) using CONNECT_BY_ROOT, but since I reverse the way the hierarchical query works (reverse the prior in connect by and the start with), this function (CONNE…

How to extract date from a long string in SQL Server

I a long string like below in my column and I need to extract only the date (2021-07-05) from it. Could anyone please help? Answer We can use PATINDEX with SUBSTRING here: Demo The call to PATINDEX above finds the starting position of the date, while SUBSTRING takes 10 characters from that position.