I need to store data(float) from 20,000 sensors once a second. I originally wanted to create the following tableļ¼ time sensor 1 sensor 2 ... sensor 20000 2024-09-06 13:00:00 1.2 5.3 .... 2.0 But then I found a table cannot…
I'm creating a statistic reporting tool and facing an issue related to memory due to a high query result (application server not responding due to RAM is full). I can't restrict the query result by limit or where clause due…
Example tables would be: object id name 0 obj0 1 obj1 2 obj2 attr id description 0 attr0 1 attr1 2 attr2 link o_id a_id 0 0 0 1 0 2 1 1 I now want to generate a SQL…
My requirement is similar to this question & answer PostgreSQL - Calculate SUM() of COUNT() But need the total by another column I have something similar to this create table Item ( ItemID INTEGER not null, ItemCode NCHAR(10) not null,…
I'm trying to use this to get contents of a specific table: let tablename = req.body.login connection.query('SELECT * FROM ?', tablename, (err, rows) => { if (err) throw err res.send(rows) }) But due to tablename being a string, it gets…
I have query like select billing_number, created, amount_total_sum, days, country, status, check_in_date, concat(elements->> 'isPossible', elements-> 'UTCDateFrom' ->> 'date', ' - ', elements-> 'UTCDateTo' ->> 'date' ) from (select o.billing_number, o.created, o.amount_total_sum, t.check_in_date, t.check_out_date - t.check_in_date as days, t.hotel_country as country,…
Image I have the following table: (in reality there are more columns) user_id | product_id ---------|------------ 1| 1 1| 2 1| 3 2| 2 2| 3 Basically, I need to copy all rows with user_id = 1 but change it…
Lets say there is a table with three columns and a million lines. How can I write a SQL statement where I get 20.000 lines, but with the restriction that a column (the second column) never has the same values?…
I have a mysql table which has two columns id and attendancetime, I want to select count(id) hourly. id attendancetime 1 1725256398 2 1725258398 3 1725264581 4 1725277777 5 1725277777 6 1725277777 7 1725298931 8 1725299156 9 1725299156 My expected…
i have the following tables: tenants: tenantId (UUID) invoiceAddress (TEXT) packages: packageId needsInvoice tenants_and_packages: tenantsAndPackagesId tenantId packageId This is a M2N-Mapping between Tenants and Packages. What is the problem? I want to achieve the following "Check"-Logic. I want to make…