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Questions tagged [concat]

Refers to the joining of two or more elements into a single element.

Concatenation refers to the joining of two or more elements into a single element. In programming, this can refer to string concatenation, which joins multiple strings into a single string, or array concatenation, where one or more arrays are combined(mostly appended) to make a new array. In some cases there are specific concatenation functions that combine elements along a specified dimension (horizontally, or vertically for example), replicate and tile existing elements, and so forth.

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How to concatenate string variables in Bash

In PHP, strings are concatenated together as follows: $foo = "Hello"; $foo .= " World"; Here, $foo becomes "Hello World". How is this accomplished in Bash?
Strawberry
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Can I concatenate multiple MySQL rows into one field?

Using MySQL, I can do something like: SELECT hobbies FROM peoples_hobbies WHERE person_id = 5; My Output: shopping fishing coding but instead I just want 1 row, 1 col: Expected Output: shopping, fishing, coding The reason is that I'm selecting…
Dean Rather
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Which is the preferred way to concatenate a string in Python?

Since Python's string can't be changed, I was wondering how to concatenate a string more efficiently? I can write like it: s += stringfromelsewhere or like this: s = [] s.append(somestring) later s = ''.join(s) While writing this question, I…
Max
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Merge two dataframes by index

I have the following dataframes: > df1 id begin conditional confidence discoveryTechnique 0 278 56 false 0.0 1 1 421 18 false 0.0 1 > df2 concept 0 A 1 B How do…
brucezepplin
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How do I concatenate strings in Swift?

How to concatenate string in Swift? In Objective-C we do like NSString *string = @"Swift"; NSString *resultStr = [string stringByAppendingString:@" is a new Programming Language"]; or NSString *resultStr=[NSString stringWithFormat:@"%@ is a new…
Rajneesh071
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MySQL CONCAT returns NULL if any field contain NULL

I have following data in my table "devices" affiliate_name affiliate_location model ip os_type os_version cs1 inter Dell 10.125.103.25 Linux Fedora cs2 inter …
neeraj
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String concatenation in MySQL

I am using MySQL and MySQL Workbench 5.2 CE. When I try to concatenate 2 columns, last_name and first_name, it doesn't work : select first_name + last_name as "Name" from test.student
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SQL UPDATE all values in a field with appended string CONCAT not working

Here is what I want to do: current table: +----+-------------+ | id | data | +----+-------------+ | 1 | max | | 2 | linda | | 3 | sam | | 4 | henry | +----+-------------+ Mystery Query (…
Fresheyeball
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Adding two Java 8 streams, or an extra element to a stream

I can add streams or extra elements, like this: Stream stream = Stream.concat(stream1, Stream.concat(stream2, Stream.of(element)); And I can add new stuff as I go, like this: Stream stream = Stream.concat( Stream.concat( …
MarcG
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Concatenate a list of pandas dataframes together

I have a list of Pandas dataframes that I would like to combine into one Pandas dataframe. I am using Python 2.7.10 and Pandas 0.16.2 I created the list of dataframes from: import pandas as pd dfs = [] sqlall = "select * from mytable" for chunk in…
Whitebeard
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Is there any haskell function to concatenate list with separator?

Is there a function to concatenate elements of a list with a separator? For example: > foobar " " ["is","there","such","a","function","?"] ["is there such a function ?"] Thanks for any reply!
Fopa Léon Constantin
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Concatenate strings in Less

I think this is not possible, but I thought I ask in case there is a way. The idea is that I have a variable for path to web resource folder: @root: "../img/"; @file: "test.css"; @url: @root@file; .px { background-image: url(@url); } I get…
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Prepend text to beginning of string

What is the fastest method, to add a new value at the beginning of a string?
mate64
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How to use GROUP_CONCAT in a CONCAT in MySQL

If I have a table with the following data in MySQL: id Name Value 1 A 4 1 A 5 1 B 8 2 C 9 how do I get it into the following format? id Column 1 …
Biswa
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MySQL select with CONCAT condition

I'm trying to compile this in my mind.. i have a table with firstname and lastname fields and i have a string like "Bob Jones" or "Bob Michael Jones" and several others. the thing is, i have for example Bob in firstname, and Michael Jones in…
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