My database character set is AL32UTF8 and national character set AL16UTF16. I need to store in a table numeric values of some characters according to db character set and later on display a specific character using numeric value. I had some problems with understanding how this encoding works (differences between unistr, chr, ascii functions and so on), but eventually I found website where the following code was used:
chr(ascii(convert(unistr(hex), AL32UTF8)))
And it works fine when hex code is smaller than 1000 when I use for example:
chr(ascii(convert(unistr('\1555'), AL32UTF8)))
chr(ascii(convert(unistr('\1556'), AL32UTF8)))
it returns the same ascii value (ascii(convert(unistr('\hex >= 1000'), AL32UTF8))). Could anyone look at this and try to explain what's the reason? I really thought I understood how it works, but now I'm confused a bit.
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I'm using the power bi snowflake connector to import data from various tables.
While it works for some tables, it fails for a particular table with special character.
This is the error I get.
Can you help?
Best
I suspect that you have Windows-1252 "Latin 1 Windows" encoded data, Microsoft's embrace-and-extend version of iso-8859-1/ECMA-94. Somehow the data presents itself to the Power BI connector as utf8 when it isn't. When everything is correctly declared, the right software (ICU?) will correctly convert into Unicode and encode into utf8 before shipping the data to Snowflake.
You've got two choices:
Fix at the source (eg correct or declare correct encoding), or
Import as binary data and try to fix after arrival in Snowflake.
My best advise is 1. - to reencode it into utf8 before importing to Snowflake.
You can't put something into a text field that isn't a sequence of valid characters. And in this case, you've got erroneous data that are not valid characters, so it is not possible to store as text.
How can this be? It is all about encoding. An utf8 character is a chained byte sequence of up to 6 bytes that is decoded into a 1-5 significant byte Unicode character codepoint (skintone emojis are examples of long byte sequences). The starting byte tells how long the utf8 sequence is, and the following bytes all contain two continuation bits 10*. If the starting byte is invalid or the correct number of follow-up bytes don't have the continuation bits, you have an invalid utf8 encoding.
And how can this happen? There are character encodings where every byte sequence is legal, like the 8-bit iso-8859-1 "ISO latin 1" or its extended cousin Windows-1252. If you declare that this sequence of byte is utf8 and not iso-8859-1, you've suddenly got a sequence of bytes that may contain invalid utf8 (because it's really Windows-1252 encoding).
As of your error message, there is no legal utf8 character encoding starting with the byte HEX(92), which is a "follow-up" byte.
I need to sort some string of Japanese/Chinese string. I am using UTF16 format here. to start with sorting, i am first normalising its character by using tolower function. but this function giving me same reply (val:31) for some characters. I tried using toupper function as well but there was no change.If I first convert UTF-16 to UTF-8 function then things start working correctly.Could any one help me what I am doing wrong.This bug is limited to these language only.
If I convert UTF-16 to UTF-8 then things starting working correctly.
When testing my code that uses a routine that checks for chars to show using an ASCII value routine, my program should drop control chars but keep chars that may be entered by the user. It seems that while the ASCII value routine is called "ascii", it does not just return ascii values: giving it a char of ƒ returns 402.
For example have found this web site
but it doesn't have ƒ 402 that I can see.
Need to know whether there are other ascii codes above 402 that I need to test my code with. The character set used internally by the software that 'ascii' is written in uses UCS2. The web site found doesn't mention USC2.
There are probably many interpretations ouf »Control Character« out there, but I'll assume you mean C0 and C1 control characters (includes references to the relevant Unicode Standards).
The commonly used 32-bit integer representation of Unicode characters in general is the codepoint notation: »U+« followed by a at least 4 digit positive hex number, which you will find near mentions of characters, e.g. as in »U+007F (delete)«. The result of your »ASCII value« routine will probably be this number without the »U+«;
UCS-2 is a specific encoding for Unicode characters, which you probably won't need to care about directly), and is equivalent to Unicode codepoints for all characters within the the range of the BMP only.
Trying to save models and i get a:
java.sql.SQLException: Incorrect string value: ...
Saving a text like "jedna dva tři kachna dům a kachní maso"
I'm using default.url="jdbc:mysql://[url]/[database]?characterEncoding=UTF-8"
řů have no encoding in latin1; áõ do. That suggests that CHARACTER SET latin1 is involved somewhere. Let's see SHOW CREATE TABLE.
C599, etc, are valid utf8 encodings for the corresponding characters.
? occurs when the destination character set cannot represent the character. Again, this points to the column/table being latin1, when it should be utf8 (or utf8mb4).
More discussion, and for debugging similar situations: Trouble with utf8 characters; what I see is not what I stored
Probably has some special character, and the UTF-8 encode that you are forcing may cause some error.
This ASCII string has the following text:
String:
jedna dva tři kachna dům a kachní maso
ASCII:
'jedna dva t\xc5\x99i kachna d\xc5\xafm a kachn\xc3\xad maso'
I have a procedure that imports a binary file containing some strings. The strings can contain extended ASCII, e.g. CHR(224), 'à'. The procedure is taking a RAW and converting the BCD bytes into characters in a string one by one.
The problem is that the extended ASCII characters are getting lost. I suspect this is due to their values meaning something else in UTF8.
I think what I need is a function that takes an ASCII character index and returns the appropriate UTF8 character.
Update: If I happen to know the equivalent Oracle character set for the incoming text can I then convert the raw bytes to UTF8? The source text will always be single byte.
There's no such thing as "extended ASCII." Or, to be more precise, so many encodings are supersets of ASCII, sharing the same first 127 code points, that the term is too vague to be meaningful. You need to find out if the strings in this file are encoded using UTF-8, ISO-8859-whatever, MacRoman, etc.
The answer to the second part of your question is the same. UTF-8 is, by design, a superset of ASCII. Any ASCII character (i.e. 0 through 127) is also a UTF-8 character. To translate some non-ASCII character (i.e. >= 128) into UTF-8, you first need to find out what encoding it's in.