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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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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...
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 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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CSS - Expand float child DIV height to parent's height
... & best solution and very flexible - but unsupported by IE9 and older.
table or display: table: very simple, very compatible (pretty much every browser ever), quite flexible.
display: inline-block; width:50% with a negative margin hack: quite simple, but column-bottom borders are a little trick...
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 :
1 Answer
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Only read selected columns
...hs (7 columns) for each year of the data below, for example by using read.table() ?
4 Answers
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sql server invalid object name - but tables are listed in SSMS tables list
.... However the SSMS intellisense does not recognize more than half of the tables which have been created.
16 Answers
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FIND_IN_SET() vs IN()
I have 2 tables in my database. One is for orders, and one is for companies.
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Update multiple columns in SQL
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Try this:
UPDATE table1
SET a = t2.a, b = t2.b, .......
FROM table2 t2
WHERE table1.id = t2.id
That should work in most SQL dialects, excluding Oracle.
And yes - it's a lot of typing - it's the way SQL does this.
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