How to view Oracle table column character set? - oracle

In Oracle, we can use desc to return the column width of each column.
Are there any commands that we can retrieve the characterset of each column?
(for example, AL32UTF8, WE8MSWIN1252)
Thank you very much.

A column doesn't have a character set in Oracle. A database has a character set and a national character set. All char, varchar2, and clob columns use the database character set. All nchar, nvarchar2, and nclob columns use the national character set.
You can see both character sets by running
SELECT *
FROM v$nls_parameters
WHERE parameter LIKE '%CHARACTERSET'

Related

How to store Japanese character in ORACLE DB without changing type of column VARCHAR2

I want to insert Japanese characters into a VARCHAR2 column type without changing this type to NVARCHAR.
Is it possible ?
Here are the characteristics of my DB (and without changing these characteristics too)
Thank you for help.

national characters in Oracle

we are using Oracle 19c
there are setting in nls_database_parameters
nls_nchar_characterset is UTF8
nls_charchterset is WE8ISO8859P15
I have a table with one column of varchar2 and another column of nvarchar2
I try to insert in both column the same letter,non english ,for example ş and it is not wotking but if I try another non english letter in my language like ž then is is working in both columns. Another colleagues of mine can not insert any letter correctly using the same database user. I don't understand this behavior,what defines what you can insert as national character?
we receive a big list of different cities in different languages. What is the best way to insert all of them correctly?

Can't insert string unicode(1000) to nvarchar2(2000) column in oracle

I have problem.Please give me the solution.
When i insert string unicode about 1000 character to nvarchar2(2000) column in oracle.Then problem:
error code: ORA-01704: string literal too long.
i get string data from enviroment server and insert to databsae local.Is there any difference here, encode utf-8,.... ?
Thank for answer
You can look this,
-Use NCHAR and NVARCHAR2 datatypes to store Unicode characters
-Keep WE8ISO8859P1 as the database character set
-Use AL16UTF16 as the national character set
-https://docs.oracle.com/cd/B19306_01/server.102/b14225/ch6unicode.htm#i1007297 .

Declaring a CLOB in an Oracle database with a custom charset

Is it possible to declare a UTF-8 CLOB if the database is set up with the following character sets?
PARAMETER VALUE
NLS_CHARACTERSET CL8ISO8859P5
NLS_NCHAR_CHARACTERSET AL16UTF16
I tried passing a charset name to the declaration, but it looks like it can only accept references to character sets of other objects.
declare
clob_1 clob character set "AL32UTF8";
begin
null;
end;
/
I don't think this is possible, see PL/SQL Language Fundamentals
PL/SQL uses the database character set to represent:
Stored source text of PL/SQL units
Character values of data types CHAR, VARCHAR2, CLOB, and LONG
So, in your case you have to use NCLOB which uses AL16UTF16 or try a workaround with BLOB. However, this might become cumbersome.
As far as I can tell, you can't do that.
Database character set is defined during database creation (and can't be changed unless you recreate the database) and all character datatype columns store data in that character set.
Perhaps you could try with NCLOB data type, where "N" represents "national character set" and it'll store Unicode character data.
Unicode is a universal encoded character set that can store
information in any language using a single character set

Oracle: query with 'N' function - which datatype should I use?

I have created an Oracle table with an indexed varchar2 column, called 'ID'.
A software I'm using is reading this table, but instead of running queries like
select * from table_name where ID='something'
it does (notice the extra "N" before the value)
select * from table_name where ID=N'something'
which is causing some kind of character conversion.
The problem is that, while the 1st query is performing a range scan, the 2nd is performing a full table scan.
Since I cannot modify the queries that this software is running, which data type should I use, instead of varchar2, so that the conversion performed by the 'N' function does not imply a full table scan?
The prefix N before the string is used to specify a NVARCHAR2 or NCHAR datatype.
When comparing NVARCHAR2s to VARCHAR2s, Oracle converts the VARCHAR2 variable to NVARCHAR2. This is why you are experiencing a FULL SCAN.
Use a NVARCHAR2 column instead of a VARCHAR2 in your table if you can't modify the query.

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