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Tag: mysql

MySQL Default Record from Table

I use MySQL 5.6 and I have 3 tables. Two of them are a list of data, and the third table is used for a relationship between them. In the third table I would like to identify a default record for each id1, so I added a column named predt to let me know which record is the default one.

Finding Similar People’s Names from Database

I have a table in MySql with names in it. I am trying to, given an input name, find all similar names in the table. I’ve heard a lot about Levenshtien/Damerau–Levenshtein distance, but it doesn’t seem like it would work well for this, I’ll explain my reasoning later. To elaborate: User input…

Mysql When then and temp variable. Explanation

I have this sql query that I am trying to understand. Can I get a line by line explanation please. I know the first line Initialise variable. Second line gets the minimum value. Answer The variables are enumerating the rows for each occupation separately. You can see this by running the subquery to see the re…

How to merge rows in sql

I am trying to understand how to merge two rows (which are the same) into one. They both have data that needs to be in the same row but the raw data currently has split them into two rows. Essentially,…

Create a left join with raw string data

I have a list of e-mails in a text file and a Person table with an email column. I need to know which of the emails are in the table, and which are not. So I was thinking in creating a query and do some kind of left join in my raw e-mail data with the Person table. Now, I

elect data from related tables with duplicate columns

I have 3 tables. news rubrics parent_id is key for id parent in table rubrics. And “news_rubriks” How I can select news which apply to rubrics.id and rubrics.parent_id ? Answer If I understand correctly, you want to apply a filter to both the rubrik id and the parent. Say if you are searching for …