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How do you add an array to another array in Ruby and not end up with a multi-dimensional result?
... [1,2,'foo','bar'].
I'm doubtless forgetting some approaches, but you can concatenate:
a1.concat a2
a1 + a2 # creates a new array, as does a1 += a2
or prepend/append:
a1.push(*a2) # note the asterisk
a2.unshift(*a1) # note the asterisk, and that a2 is the receiver
or...
console.log timestamps in Chrome?
...2) > click the three-dot menu in the top right > click settings > select Preferences in the left menu > check show timestamps in the Console section of the settings screen (top right)
– tekiegirl
Sep 4 '18 at 9:52
...
UPDATE multiple tables in MySQL using LEFT JOIN
...= t1.id
SET t1.col1 = newvalue
WHERE t2.id IS NULL
Note that for a SELECT it would be more efficient to use NOT IN / NOT EXISTS syntax:
SELECT t1.*
FROM t1
WHERE t1.id NOT IN
(
SELECT id
FROM t2
)
See the article in my blog for performance details...
Drop multiple tables in one shot in mysql
... of tables to be deleted.
Get table using the below
For sql server - SELECT CONCAT(name,',') Table_Name FROM SYS.tables;
For oralce - SELECT CONCAT(TABLE_NAME,',') FROM SYS.ALL_TABLES;
Copy and paste the table names from the result set and paste it after the DROP command.
...
Append an array to another array in JavaScript [duplicate]
...embers of arrays 2 and 3 at once.
or...
array1.push.apply(array1, array2.concat(array3));
To deal with large arrays, you can do this in batches.
for (var n = 0, to_add = array2.concat(array3); n < to_add.length; n+=300) {
array1.push.apply(array1, to_add.slice(n, n+300));
}
If you ...
How to get first and last day of previous month (with timestamp) in SQL Server
...
select DATEADD(MONTH, DATEDIFF(MONTH, 0, GETDATE())-1, 0) --First day of previous month
select DATEADD(MONTH, DATEDIFF(MONTH, -1, GETDATE())-1, -1) --Last Day of previous month
...
Cartesian product of multiple arrays in JavaScript
...aScript, no lodash, underscore or other libraries:
let f = (a, b) => [].concat(...a.map(a => b.map(b => [].concat(a, b))));
let cartesian = (a, b, ...c) => b ? cartesian(f(a, b), ...c) : a;
Update:
This is the same as above but improved to strictly follow the Airbnb JavaScript Style Gui...
Fast permutation -> number -> permutation mapping algorithms
...Position[i], iOutPosition[i] + 1);
this.sOutStr = this.sOutStr.concat(sTempStr);
}
return this.sOutStr;
}
public int[] PermGetIntArray(int iIndex)
{
if (!this.bGoodToGo) return null;
if (!this.PermEvaluate(iIndex)) return null ;
return...
Why use String.Format? [duplicate]
Why would anyone use String.Format in C# and VB .NET as opposed to the concatenation operators ( & in VB, and + in C#)?
...
Copy array by value
...ually show that var arr2 = arr1.slice() is just as fast as var arr2 = arr1.concat(); JSPerf: jsperf.com/copy-array-slice-vs-concat/5 and jsperf.com/copy-simple-array . The result of jsperf.com/array-copy/5 kind of surprised me to the point I am wondering if the test code is valid.
...