I want to count something like this: input list: AAA female 1 AAA female 2 BBB male 2 BBB male 1 AAA male 1 output list: AAA male 1 AAA female 3 BBB male 3 Sorry, my english is not good,…
How to optimize a MySQL query which is taking 10 sec to fetch results
I have a MySQL database. I have a table in it which has around 200000 rows. I am querying through this table to fetch the latest data.Query select * from `db`.`Data` where floor = “floor_value”…
Does Oracle Apex support table partitioning?
I’m new to Oracle and Apex, and I’m building a table that will potentially become very large over time. It would be ideal to partition by date range, and then subpartition by hash. Does Apex support …
How to speed up BETWEEN operation on several million items?
I have table (very simplified) in MySQL: id | name | datetime | label 1 | a | 2019-10-01 10:00:01 | null 2 | a1 | 2019-10-01 10:00:03 | null 3 | a2 | 2019-10-…
C#: How to pass parmeterize values to System.Data.Entity.SqlSquery
I’m going to execute SQL query directly on database. I’ve define connection to my database using: System.Data.Entity.DbContext rawDbContext = new DbContext(connectionString); I don’t want to insert …
Using Two Tables to give one output
Table: Person +————-+———+ | Column Name | Type | +————-+———+ | PersonId | int | | FirstName | varchar | | LastName | varchar | +————-+———+ …
duplicate data being return with varied # of results in cross join
I created a database for a clothing brand. The products consists of 3 tables: products, product_photos, inventory. The issue I’m having pertains to the amount of results in the product_photos, …
What is the result of DateTime operation in MySQL
I tried the following SQL query. select start_time, end_time, end_time-start_time from orders This printed the following output. start_time |end_time |end_time-start_time … …
Sql Query / Calculate rank for values based on date and id
For each date and id we have to give the rank to values in decreasing order. Below is the Input Table. Output should look like below: Answer You can use RANK(), partitioning on date and id and ordering by value descending: Output: Demo on SQLFiddle This query will run on all the DBMS you have tagged your question with.
how to select first and last row in 1 query after Filtering and then carry out calculation between the values of two values in one query
I’m using T-SQL 2014 Suppose I have a stock price chart as follow I want to write efficient code for a stored function to display the Open price at the start, Close price at the end, and the difference between Close and Open. Is it possible to do that in one query? The query seems easy but it turned out