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How do you concatenate Lists in C#?
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Concat returns a new sequence without modifying the original list. Try myList1.AddRange(myList2).
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How to prepend a string to a column value in MySQL?
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You can use the CONCAT function to do that:
UPDATE tbl SET col=CONCAT('test',col);
If you want to get cleverer and only update columns which don't already have test prepended, try
UPDATE tbl SET col=CONCAT('test',col)
WHERE col NOT LIKE ...
Compare two DataFrames and output their differences side-by-side
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Is it possible to select only different rows? In this case how do I select second and third row without selecting first row (111)?
– shantanuo
May 4 '18 at 8:13
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Comparing strings with == which are declared final in Java
... question about strings in Java. The following segment of simple code just concatenates two strings and then compares them with == .
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How to merge two arrays in JavaScript and de-duplicate items
... just merge the arrays (without removing duplicates)
ES5 version use Array.concat:
var array1 = ["Vijendra", "Singh"];
var array2 = ["Singh", "Shakya"];
console.log(array1.concat(array2));
ES6 version use destructuring
const array1 = ["Vijendra","Singh"];
const array2 = ["Singh", "Shakya"...
Combine multiple Collections into a single logical Collection?
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With Guava, you can use Iterables.concat(Iterable<T> ...), it creates a live view of all the iterables, concatenated into one (if you change the iterables, the concatenated version also changes). Then wrap the concatenated iterable with Iterables.unmodi...
SSMS插件开发指南 - C/C++ - 清泛网 - 专注C/C++及内核技术
...nt;
if (document != null)
{
TextSelection selection = (TextSelection)document.Selection;
selection.Insert(text, (Int32)EnvDTE.vsInsertFlags.vsInsertFlagsContainNewText);
}
}
#region 私有方法
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How many String objects will be created when using a plus sign?
...iteLine(result);
}
then the compiler seems to emit the code using String.Concat as @Joachim answered (+1 to him btw).
If you define them as constants, e.g.:
const String one = "1";
const String two = "2";
const String result = one + two + "34";
or as literals, as in the original question:
Str...
Comparing two dataframes and getting the differences
...to find changes, but symmetric difference. For that, one approach might be concatenate dataframes:
>>> df = pd.concat([df1, df2])
>>> df = df.reset_index(drop=True)
group by
>>> df_gpby = df.groupby(list(df.columns))
get index of unique records
>>> idx = [...
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...