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SQL MAX of multiple columns?

... for those who came here looking for a MySQL way, take a look to @bajafresh4life reply: stackoverflow.com/a/331873/1412157 – LucaM May 22 '15 at 13:23 ...
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Counting DISTINCT over multiple columns

...INCT concat(DocumentId, DocumentSessionId)) FROM DocumentOutputItems; In MySQL you can do the same thing without the concatenation step as follows: SELECT count(DISTINCT DocumentId, DocumentSessionId) FROM DocumentOutputItems; This feature is mentioned in the MySQL documentation: http://dev.my...
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What is the difference between a schema and a table and a database?

...ction of tables. A DBMS (Database Management System) is the software (like MySQL, SQL Server, Oracle, etc) that manages and runs a database. share | improve this answer | fol...
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How to drop all user tables?

... Being new to Oracle and I'm more familiar with MySQL; reseting a DB seems difficult. IN MySQL a USER is separate to a DATABASE. DROP USER username CASCADE worked for me. But in MySQL all I would have to do is DROP DATABASE and create a new one – gawp...
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How do I UPDATE from a SELECT in SQL Server?

... @CharlesWood yeah. I have the same question in MySQL. It would be great if someone knows how to implement it to MySQL and share with everyone. I'm sure lots of people are looking for a MySQL version solution – Roger Ray Nov 27 '13 at...
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When to use a key/value store such as Redis instead/along side of a SQL database?

.... I did recently for one gps tracking system which was previously built on mysql as a database. ADVANTAGE Every time the tracker broadcast data I do not need to open mysql connection and store on it. We can save it on redis and later migrate to mysql using some other process. This will avoid conc...
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How to implement LIMIT with SQL Server?

I have this query with MySQL: 18 Answers 18 ...
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setting multiple column using one update

How to set multiple columns of a table using update query in mysql? 2 Answers 2 ...
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How can I transform string to UTF-8 in C#?

... If you want to save any string to mysql database do this:-> Your database field structure i phpmyadmin [ or any other control panel] should set to utf8-gerneral-ci 2) you should change your string [Ex. textbox1.text] to byte, therefor 2-1) define byte[]...
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How to change a nullable column to not nullable in a Rails migration?

... This worked for me. Using MySql locally. When pushed and ran app in Heroku (Postgres) it crapped on column that was not null when I was writing it a null - rightfully so. Only "change_column_null" would work could not use "change_column ... :null =&gt...