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Select multiple columns in data.table by their numeric indices
...ltiple columns using a vector of their numeric indices (position) in data.table ?
5 Answers
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Insert Data Into Temp Table with Query
...query that outputs current data, and I would like to insert it into a Temp table, but am having some issues doing so. Would anybody have some insight on how to do this?
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Search for all occurrences of a string in a mysql database [duplicate]
...how to locate all occurrences of a url in a database. I want to search all tables and all fields. But I have no idea where to start or if it's even possible.
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Adding multiple columns AFTER a specific column in MySQL
I need to add multiple columns to a table but position the columns after a column called lastname .
10 Answers
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What is SELF JOIN and when would you use it? [duplicate]
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You use a self join when a table references data in itself.
E.g., an Employee table may have a SupervisorID column that points to the employee that is the boss of the current employee.
To query the data and get information for both people in one row,...
What is causing ERROR: there is no unique constraint matching given keys for referenced table?
Below example table structure gives an ERROR: there is no unique constraint matching given keys for referenced table, and having stared at it for while now I can't figure out why this error arises in this situation.
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Querying data by joining two tables in two database on different servers
There are two tables in two different databases on different servers, I need to join them so as to make few queries. What options do I have? What should I do?
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Are soft deletes a good idea? [duplicate]
...ow have to include a WHERE IsDeleted = false clause in every query on this table (and so much worse if you're JOINing these tables). A mistake here would be caught as soon as a user or tester noticed a deleted record showing up again, which might take some time. Also, it would be easy for a develo...
Adding a new value to an existing ENUM Type
I have a table column that uses an enum type. I wish to update that enum type to have an additional possible value. I don't want to delete any existing values, just add the new value. What is the simplest way to do this?
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mysql -> insert into tbl (select from another table) and some default values [duplicate]
As the title says, I am trying to insert into one table selecting values from another table and some default values.
5 Ans...