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Add a column with a default value to an existing table in SQL Server
...ed for Existing Records.
If your Column is NOT NULL, then it will automatically use the Default Value
for all Existing Records, whether you specify WITH VALUES or not.
How Inserts work with a Default-Constraint:
If you insert a Record into SomeTable and do not Specify SomeCol's value, then it...
How to replace a character with a newline in Emacs?
...
C-q is really quote-insert which quotes the next character.
– Joe Casadonte
Mar 5 '09 at 2:17
2
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Passing references to pointers in C++
As far as I can tell, there's no reason I shouldn't be allowed to pass a reference to a pointer in C++. However, my attempts to do so are failing, and I have no idea why.
...
Convert string to symbol-able in ruby
Symbols are usually represented as such
7 Answers
7
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Is it possible to modify variable in python that is in outer, but not global, scope?
...ld a temporary scope. It's like the mutable but a bit prettier.
def outer_fn():
class FnScope:
b = 5
c = 6
def inner_fn():
FnScope.b += 1
FnScope.c += FnScope.b
inner_fn()
inner_fn()
inner_fn()
This yields the following interactive output:
>>> outer...
Select unique or distinct values from a list in UNIX shell script
...n the following input:
class
jar
jar
jar
bin
bin
java
uniq will output all lines exactly once:
class
jar
bin
java
uniq -d will output all lines that appear more than once, and it will print them once:
jar
bin
uniq -u will output all lines that appear exactly once, and it will print them ...
Intel HAXM installation error - This computer does not support Intel Virtualization Technology (VT-x
I have an issue with my HAXM installation. Here is the thing. I got this error every single time I tried to install HAXM for my computer:
...
@UniqueConstraint and @Column(unique = true) in hibernate annotation
... The same aplies for group.
On the other hand,
@Table(
name = "product_serial_group_mask",
uniqueConstraints = {@UniqueConstraint(columnNames = {"mask", "group"})}
)
Implies that the values of mask + group combined should be unique. That means you can have, for example, a record with mask...
How to use range-based for() loop with std::map?
...
Each element of the container is a map<K, V>::value_type, which is a typedef for std::pair<const K, V>. Consequently, in C++17 or higher, you can write
for (auto& [key, value]: myMap) {
std::cout << key << " has value " << value << std:...
Rank function in MySQL
... (SELECT @curRank := 0) r
ORDER BY age;
The (SELECT @curRank := 0) part allows the variable initialization without requiring a separate SET command.
Test case:
CREATE TABLE person (id int, first_name varchar(20), age int, gender char(1));
INSERT INTO person VALUES (1, 'Bob', 25, 'M');
INSERT I...