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Mapping many-to-many association table with extra column(s)
My database contains 3 tables:
User and Service entities have many-to-many relationship and are joined with the SERVICE_USER table as follows:
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How do I drop table variables in SQL-Server? Should I even do this?
I have a table variable in a script (not a stored procedure). Two questions:
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Reset auto increment counter in postgres
I would like to force the auto increment field of a table to some value, I tried with this:
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Adding a column to an existing table in a Rails migration
...e the add_column line completely (that code is trying to add a column to a table, before the table has been created, and your table creation code has already been updated to include a t.string :email anyway).
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How to create composite primary key in SQL Server 2008
I want to create tables in SQL Server 2008, but I don't know how to create composite primary key. How can I achieve this?
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PostgreSQL function for last inserted ID
In PostgreSQL, how do I get the last id inserted into a table?
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What is SYSNAME data type in SQL Server?
... be honest. It is mainly used by Microsoft when building the internal sys tables and stored procedures etc within SQL Server.
For example, by executing Exec sp_help 'sys.tables' you will see that the column name is defined as sysname this is because the value of this is actually an object in itsel...
Is 'switch' faster than 'if'?
...ons a compiler can make on a switch. I don't think the oft-mentioned "jump-table" is a very useful one though, as it only works when the input can be bounded some way.
C Pseudocode for a "jump table" would be something like this -- note that the compiler in practice would need to insert some form o...
What's the difference between a catalog and a schema in a relational database?
...if you query the information_schema views, you'll find that values in the "table_catalog" column map to the name of a database.
If you find your platform using catalog in a broader way than any of these three definitions, it might be referring to something broader than a database--a database cl...
How to remove a lua table entry by its key?
I have a lua table that I use as a hashmap, ie with string keys :
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