Loading data in hive table with multiple charsets - character-encoding

I am facing issues where i have multiple files with different charsets, say one file has Chinese charsets and other has French Charsets, how can i load them in a single hive table? I searched online and found this :-
ALTER TABLE mytable SET SERDEPROPERTIES ('serialization.encoding'='SJIS');
With this i can handle charsets for one of the file either Chinese or French. Is there a way to handle both charsets once?
[UPDATE]
Okay i am using RegexSerde for fixed width file alongside encoding scheme being used is - ISO 8859-1. Seems Regex Serde is not taking this encoding scheme into account and splitting the characters considering default UTF-8 encoding scheme. Is there a way to take encoding scheme into account with Regex serde.

I am not sure if this is possible (i think it isn't based on https://github.com/apache/hive/blob/master/serde/src/java/org/apache/hadoop/hive/serde2/AbstractEncodingAwareSerDe.java). A workaround could be create two tables with different enconding and create a view on top of that.

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Best practices for creating a CSV file?

I am working in Swift although perhaps the language is not as relevant, and I am creating a relatively simple CSV file.
I wanted to ask for some recommendations in creating the files, in particular:
Should I wrap each column/value in single or double quotes? Or nothing? I understand if I use quotes I'll need to escape them appropriately in case the text in my file legitimately has those values. Same for \r\n
Is it ok to end each line with \r\n ? Anything specific to Mac vs. Windows I need to think about?
What encoding should I use? I'd like to make sure my csv file can be read by most readers (so on mobile devices, mac, windows, etc.)
Any other recommendations / tips to make sure the quality of my CSV is ideal for most readers?
I have a couple of apps that create CSV files.
Any column value that contains a newline or the field separator must be enclosed in quotes (double quotes is common, single quotes less so).
I end lines with just \n.
You may wish to give the user some options when creating the CSV file. Let them choose the field separator. While the comma is common, a tab is also common. You can also use a semi-colon, space, or other characters. Just be sure to properly quote values that contain the chosen field separator.
Using UTF-8 encoding is arguably the best choice for encoding the file. It lets you support all Unicode characters and just about any tool that supports CSV can handled UTF-8. It avoid any issues with platform specific encodings. But again, depending on the needs of your users, you may wish to give them the choice of encoding.

tFuzzyMatch apparently not working on Arabic text strings

I have created a job in talend open studio for data integration v5.5.1.
I am trying to find matches between two customer names columns, one is a lookup and the other contain dirty data.
The job runs as expected when the customer names are in english. However, for arabic names, only exact matches are found regardless of the underlying match algorithm i used (levenschtein, metaphone, double metaphone) even with loose bounds for the levenschtein algorithm min 1 max 50).
I suspect this has to do with character encoding. How should I proceed? any way I can operate using the unicode or even UTF-8 interpretation in Talend?
I am using excel data sources through tFileInputExcel
I got it resolved by moving the data to mysql with a UTF-8 collation. Somehow Excel input wasn't preserving the collation.

retrieve txt content of as many file types as possible

I maintain a client server DMS written in Delphi/Sql Server.
I would like to allow the users to search a string inside all the documents stored in the db. (files are stored as blob, they are stored as zipped files to save space).
My idea is to index them on "checkin", so as i store a nwe file I extract all the text information in it and put it in a new DB field. So somehow my files table will be:
ID_FILE integer
ZIPPED_FILE blob
TEXT_CONTENT text field (nvarchar in sql server)
I would like to support "indexing" of at least most common text-like files, such as:pdf, txt, rtf, doc, docx,pdf, may be adding xls and xlsx, ppt, pptx.
For MS Office files I can use ActiveX since I alerady do it in my application, for txt files i can simply read the file, but for pdf and odt?
Could you suggest the best techinque or even a 3rd party component (not free too) that parses with "no fear" all file types?
Thanks
searching documents this way would leed to a very slow and inconvenient to use, I'd advice you produce two additional tables instead of TEXT_CONTENT field.
When you parse the text, you should extract valuable words and try to standardise them so that you
- get rid of lower/upper case problems
- get rid of characters that might be used interchangeably.
i.e. in Turkish we have ç character that might be entered as c.
- get rid of verbs that are common in the language you are dealing with.
i.e. "Thing I am looking for", "Thing" "Looking" might be in your interest
- get rid of whatever problem use face.
Each word, that has already an entry in the table should re-use the ID already given in the string_search table.
the records may look like this.
original_file_table
zip_id number
zip_file blob
string_search
str_id number
standardized_word text (or any string type with an appropriate secondary index)
file_string_reference
zip_id number
str_id number
I hope that I could give you the idea what I am thinking of.
Your major problem is zipping your files before putting them as a blob in your database which makes them unsearchable by the database itself. I would suggest the following.
Don't zip files you put in the database. Disk space is cheap.
You can write a query like this as long as you save the files in a text field.
Select * from MyFileTable Where MyFileData like '%Thing I am looking for%'
This is slow but it will work. This will work because the text in most of those file types is in plain text not binary (though some of the newer file types are now binary)
The other alternative is to use an indexing engine such as Apache Lucene or Apache Solr which will as you put it
parses with "no fear" all file types?

Is there known URI scheme or URN namespace for Unicode characters?

I need to reference to a Unicode character with a URI. Following IANA references list multiple schemes and namespaces but do not mention anything about identifiers for the Unicode characters. Does anyone know if something like this exists already?
http://www.iana.org/assignments/uri-schemes.html
http://www.iana.org/assignments/urn-namespaces/urn-namespaces.xml
I hoped to find something like
unicode://U+0394
urn:unicode://0394
http://unicode.org/unicode/0394
for the greek capital letter delta Δ.
If someone wonders, this is for a semantic web like application that uses URIs as identifiers for concepts, including concepts of the Unicode characters.
I’m afraid there is no URL or URN for referring authoritative information on a Unicode character in general. In the Unicode Standard, information about individual characters is partly in the so-called character database (mostly plain text files in specific formats), partly in the Code Charts (PDF files). Neither of them offers a way to point at an individual character. Moreover, the information there is not exhaustive: there are important remarks on individual characters information scattered around the standard.
The Decodeunicode site has individually addressable items, such as
http://www.decodeunicode.org/en/u+0394
but its information content varies a lot and is generally very limited. It is not official, and it currently contains Unicode 5.0 only.
The Fileformat.info site is much more systematic, but it, too, is unofficial. It is basically limited to formal properties and data derivable from them, plus comments extracted from the Code Charts, plus instructions on typing the character in Windows, plus information about support in fonts—but that’s quite a lot! Example:
http://www.fileformat.info/info/unicode/char/0394/
[ EDIT ] : found this URL matching your needs : http://unicode.org/cldr/utility/character.jsp?a=1F40F
.
Well, there is an URL referencing the authoritative information on the Unicode database, even though it does not describe (as said in the other answer) all the information on one specific character.
You have the following URL, pointing to the latest Unicode database. This is a simple list of existing valid Unicode characters. Some upcoming characters are missing (㋿), and you should expect it to be mutable.
https://www.unicode.org/Public/UCD/latest/ucd/UnicodeData.txt
The contents looks like the following, which isn't so practical to use as-is.
$ grep -ai kangaroo UnicodeData.txt -C 7
1F991;SQUID;So;0;ON;;;;;N;;;;;
1F992;GIRAFFE FACE;So;0;ON;;;;;N;;;;;
1F993;ZEBRA FACE;So;0;ON;;;;;N;;;;;
1F994;HEDGEHOG;So;0;ON;;;;;N;;;;;
1F995;SAUROPOD;So;0;ON;;;;;N;;;;;
1F996;T-REX;So;0;ON;;;;;N;;;;;
1F997;CRICKET;So;0;ON;;;;;N;;;;;
1F998;KANGAROO;So;0;ON;;;;;N;;;;;
1F999;LLAMA;So;0;ON;;;;;N;;;;;
1F99A;PEACOCK;So;0;ON;;;;;N;;;;;
1F99B;HIPPOPOTAMUS;So;0;ON;;;;;N;;;;;
1F99C;PARROT;So;0;ON;;;;;N;;;;;
1F99D;RACCOON;So;0;ON;;;;;N;;;;;
1F99E;LOBSTER;So;0;ON;;;;;N;;;;;
1F99F;MOSQUITO;So;0;ON;;;;;N;;;;;
You could build up a hacky « hash-based » namespace with a suffix like this, but that's definitely non-standard.
https://www.unicode.org/Public/UCD/latest/ucd/UnicodeData.txt#1F998
Since this is also tagged semantic-web, I will try to pick URIs that are easily (and permanently) dereferenceable and cannot be mistaken for a document describing that character: the data: scheme. Not only can that refer to a character in Unicode, but any encoding, and also any string thereof.
data:;charset=utf-8,%CE%94
Attempting to open this URI should result in a text/plain file with the single character as its content.
If the system accepts IRIs (as many semantic web applications do), the character can be included directly:
data:;charset=utf-8,Δ
This is mapped to the same URI as shown above, and your browser may convert it directly. Specifying UTF-8 is necessary in this case, since the mapping is not defined for other encodings.

Recommended column delimiter for Click stream data to consumed by SSIS

I am working with some click stream data and i would need to give specifications to the vendor regarding a preferred format to be consumed by SSIS.
As its URL data in the text file which column delimiter would you recommend. I was thinking pipe "|" but i realize that pipes can be used within the URL.
I did some testing to specify multiple charecters as delimiter lile |^| but when I am creating a flat file connection there is not option in SSIS. I had type these charecters. But when i went to edit the flat file connection manager it had changed to {|}^{|}. It just made me nervous to the import succeeded.
I just wanted to see if anybody has good ideas as to which would safe column delimiter to use.
Probably tab-delimited would be fairly safe, at least assuming that by "clickstream" you mean a list of URLs or something similar. But in theory any delimiter should be fine as long as the supplier quotes the data appropriately.

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