Mysql query by weekday
I want to query by weekday in a given table on a column storing dates. E.g. select * from MY_TABLE where date_column is 'Monday' I saw a DAYOFWEEK() function in mysql. But this only seems to manipulate the results of…
Mysql – The Rows Holding the Group-wise Minimun of a Certain Column, but using an additional condition
From this dataset: mysql> SELECT * FROM document_signature; +----+-------------+-------------+---------+-------+-----------+ | id | document_id | employee_id | user_id | order | status | +----+-------------+-------------+---------+-------+-----------+ | 1 | 1 | 2 | NULL | 0 | SIGNED | | 2 | 1…
Mysql – Fill up rows to count
I got the result of a query, and want to join it with a mockup table to fill the rows up to a certain number. this is an example where the query has two rows as result, but i always…
Postgresql – Basing OFFSET on another query?
My table structure is roughly as described in this post: name processed processing updated ref_time abc t f 27794395 27794160 def t f 27794395 27793440 ghi t f 27794395 27793440 jkl f f 27794395 27794160 mno t f 27794395 27793440…
is there any way to apply different filters on a mysql table based on the value of a column?
assume a table has id and date columns, is there a way to apply different date filter to each id? one way I can think of is to add a flag column that is populated with an if ladder if…
Postgresql – How to refer to one of the column inside a SQL query
I have some rows in an SQL table. I have attributes as: id, name, etc. Some of the names (in the name column) are built from some name ("xyz") and the id id name 333 regularName 555 somename.555 666 myName.666…
Mysql – Is an auto inc primary key needed here to avoid fragmentation?
I have a table such as follows: CREATE TABLE Associations ( obj_id int unsigned NOT NULL, attr_id int unsigned NOT NULL, assignment Double NOT NULL PRIMARY KEY (`obj_id`, `attr_id`), ); Now the insertion order for the rows is/will be random.…
Mysql – SQL Select all if value exists in column
I have three Table. The first Table contains a Rezipe with a id, the second Table contains the rezeptid with the ingredients and the third Table shows the ingredient with a restriction(vegan, meat...). Im looking for a way to select…
Postgresql – output a number — the number of students whose name (first_name) matches the name of at least one other student
Well, that is, there are two Johns and one Quill, you need to output the number of those people who have the same name. In one column there should be the total number of students with the same names SELECT…
Postgresql – Get sum of difference of rows in sql
I have a table with given values | id | level | value | | --- | ------ | ----- | | 1 | 30000 | 0.05 | | 2 | 100000 | 0.06 | | 3 | 120000 |…