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When should null values of Boolean be used?
..."boolean", not "boolean" (mind styling), because in Oracle you usually use char(1) null with 'T' and 'F' values. So it may (with e.g., Hibernate type adapter) be null :)
– Grzegorz Grzybek
Jun 25 '12 at 7:58
...
What is the purpose of fork()?
...hild executes this.
// new argv array for the child process
const char *argv[] = {"arg1", "arg2", "arg3", NULL};
// now start executing some other program
exec("/path/to/a/program", argv);
}
The shell spawns a child process using exec and waits for it to complete, then continues ...
Trying to embed newline in a variable in bash [duplicate]
...rting \n
p="${var1}\n${var2}"
echo -e "${p}"
echo -e interprets the two characters "\n" as a new line.
var="a b c"
first_loop=true
for i in $var
do
p="$p\n$i" # Append
unset first_loop
done
echo -e "$p" # Use -e
Avoid extra leading newline
var="a b c"
first_loop=1...
Node.js throws “btoa is not defined” error
...
The solutions posted here don't work in non-ascii characters (i.e. if you plan to exchange base64 between Node.js and a browser). In order to make it work you have to mark the input text as 'binary'.
Buffer.from('Hélló wórld!!', 'binary').toString('base64')
This gives...
Reshaping data.frame from wide to long format
...
Here is another example showing the use of gather from tidyr. You can select the columns to gather either by removing them individually (as I do here), or by including the years you want explicitly.
Note that, to handle the commas (and X's added if check.names = FALSE is not set), I am also us...
IN clause and placeholders
...mes = { "name1", "name2" }; // do whatever is needed first
String query = "SELECT * FROM table"
+ " WHERE name IN (" + makePlaceholders(names.length) + ")";
Cursor cursor = mDb.rawQuery(query, names);
Just make sure to pass exactly as many values as places. The default maximum limit of host pa...
How do I perform an insert and return inserted identity with Dapper?
...uerySingle<int>( @"
INSERT INTO [MyTable] ([Stuff]) VALUES (@Stuff);
SELECT CAST(SCOPE_IDENTITY() as int)", new { Stuff = mystuff});
Note that on more recent versions of SQL Server you can use the OUTPUT clause:
var id = connection.QuerySingle<int>( @"
INSERT INTO [MyTable] ([Stuff])
...
Removing empty lines in Notepad++
...
Should first select 'extended` in search mode.
– q0987
Apr 17 '12 at 15:47
14
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MongoDB relationships: embed or reference?
...ill tied to text messages and Ruby 1.4 strings; in other words still ASCII chars only.
– John F. Miller
Sep 8 '17 at 18:52
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show 4 more com...
How can I selectively merge or pick changes from another branch in Git?
... git rebase -i to get the original commit to edit, then git reset HEAD^ to selectively revert changes, then git commit to commit that bit as a new commit in the history.
There is another nice method here in Red Hat Magazine, where they use git add --patch or possibly git add --interactive which all...