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If vs. Switch Speed
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The compiler can build jump tables where applicable. For example, when you use the reflector to look at the code produced, you will see that for huge switches on strings, the compiler will actually generate code that uses a hash table to dispatch these....
In Postgresql, force unique on combination of two columns
I would like to set up a table in PostgreSQL such that two columns together must be unique. There can be multiple values of either value, so long as there are not two that share both.
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Align DIV's to bottom or baseline
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Use the CSS display values of table and table-cell:
HTML
<html>
<body>
<div class="valign bottom">
<div>
<div>my bottom aligned div 1</div>
<div>my bottom aligned div 2</div>
<...
In MySQL, can I copy one row to insert into the same table?
I just want to copy one row to insert into the same table (i.e., I want to duplicate an existing row in the table) but I want to do this without having to list all the columns after the "select", because this table has too many columns.
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How to check if a Constraint exists in Sql server?
...QUE, PRIMARY KEY, and/or FOREIGN KEY
SELECT *
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE CONSTRAINT_NAME='XYZ'
--Returns one row for each FOREIGN KEY constrain
SELECT *
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS
WHERE CONSTRAINT_NAME='XYZ'
--Returns one row for eac...
Combining INSERT INTO and WITH/CTE
...e a very complex CTE and I would like to insert the result into a physical table.
3 Answers
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Best way to do multi-row insert in Oracle?
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In Oracle, to insert multiple rows into table t with columns col1, col2 and col3 you can use the following syntax:
INSERT ALL
INTO t (col1, col2, col3) VALUES ('val1_1', 'val1_2', 'val1_3')
INTO t (col1, col2, col3) VALUES ('val2_1', 'val2_2', 'val2_3')
I...
How to edit data in result grid in SQL Server Management Studio
...et a query output in the result grid.
Its true that we can right click the table and say open table to get an editable table output, but what I want is editable query output, only certain rows matching for my criteria, and edit them in the result grid.
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Salting Your Password: Best Practices?
... Site-wide random salt is bad, since an attacker can precompute rainbow tables and grab your entire user database. If you don't understand this, please don't write login/security systems :) - you NEED per-user salts.
– snemarch
Mar 23 '09 at 20:52
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Create unique constraint with null columns
I have a table with this layout:
4 Answers
4
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