I am a quality analysts and I got a task to test a database function n_execute() which takes 3 parameters
1. image_name
2. image_data (byte array) this is a blob type.
3. data_created
Now my problem is that to test this function I want to call this function but don't know how to input iamge o the second parameter of this function.
I know we can do it by writing some java code which calls this function but I primarily wants to execute it through SQL editor only.
You haven't mentioned which database platform you are working with but in a SQL Server T/SQL script IMAGE data would be a binary constant. A simple example would be 0x0102030405 which represents 5 hex bytes; 01, 02, 03, 04 and 05.
Edit for PostgreSQL
For PostgreSQL take a look at the docs, Binary data types. Note;
The bytea type supports two external formats for input and output:
PostgreSQL's historical "escape" format, and "hex" format.
The PostgreSQL equivalent to my SQL Server example would be E'\\x0102030405'.
Related
I have a db2 database where I store names containing special characters. When I try to retrieve them with an internal software, I get proper results. However when I tried to do the same with queries or look into the db, the characters are stored strangely.
The documentation says that the encoding is utf-8 latin1.
My query looks something like this:
SELECT firstn, lastn
FROM unams
WHERE unamid = 12345
The user with the given ID has some special characters in his/her name: é and ó, but the query returns it as Ă© and Ăł.
Is there a way to convert the characters back to their original form with using some simple SQL function? I am new to databases and encoding, trying to understand the latter by reading this but I'm quite lost.
EDIT: Currently sending queries via SPSS Modeler with a proper ODBC driver, the database lies on a Windows Server 2016
Per the comments, the solution was to create a Windows environment variable DB2CODEPAGE=1208 , then restart, then drop and re-populate the tables.
If the applications runs locally on the Db2-server (i.e. only one hostname is involved) then the same variable can be set. This will impact all local applications that use the UTF-8 encoded database.
If the application runs remotely from the Db2-server (i.e. two hostnames are involved) then set the variable on the workstation and on the Windows Db2-server.
Current versions of IBM supplied Db2-clients on Windows will derive their codepage from the regional settings which might not always render Unicode characters correctly, so using the DB2CODEPAGE=1208 forces the Db2-client CLI drivers to use a Unicode application code page to override this.
with t (firstn) as (
values ('éó')
--SELECT firstn
--FROM unams
--WHERE unamid = 12345
)
select x.c, hex(x.c) c_hes
from
t
, xmltable('for $id in (1 to string-length($s)) return <i>{substring($s, $id, 1)}</i>'
passing t.firstn as "s" columns tok varchar(6) path '.') x(c);
C C_HEX
- -----
é C3A9
ó C3B3
The query above converts the string of characters to a table with each character (C) and its hex representation (C_HEX) in each row.
You can run it as is to check if you get the same output. It must be as described for a UTF-8 database.
Now try to comment out the line with values ('éó') and uncomment the select statement returning some row with these special characters.
If you see the same hex representation of these characters stored in the firstn column, then this means, that the string is stored appropriately, but your client tool (SPSS Modeller) can't show these characters correctly due to some reason (wrong font, for example).
I know I can do the conversion very easily using C# or any other number of programming languages, however, I want to know if I can do the conversion of a column that has EBCDIC encoded text so that the result of the query is in a readable string such as ascii encoded.
Ultimately, I will import the data into SQL Server and I know SSIS can do it, but before I do that, I want to exhaust any paths that are not SQL language.
For example a little know combination of built in functions available in DB2 SQL or SQL-Server 2008
Here is an example of data
Data as stored in DB2: 0xC6C3C3C1E3C5D9D7C9D3D360F8F840
Text: FCCATERPILL-88
The C# conversion is so easy so I included it here:
System.Text.Encoding ei = Encoding.GetEncoding(37);
textBox1.Text = ei.GetString(allBytes.ToArray())
I'm not an AS400 admin so I'm not sure what to do with what is being suggested in the comments.
I need to store binary data in single database field (DB is SQLite, it's important!). Binary data is a some one-dimensional array.One of the best way to do that is BLOB data insertion. As far as I know Matlab doesn't consist methods for BLOB data processing. How can I do that using Matlab environment? Maybe using raw SQL query?
In a raw SQLite query, a blob can be written as a x-prefixed string, with each byte representeded by a two-digit hexadecimal number:
INSERT INTO MyTable(BlobColumn) VALUES(x'0123AB');
To return a blob as text from a query, you can use the quote() function, which uses the same format:
SELECT quote(BlobColumn) FROM MyTable; --> returns the string "x'0123AB'"
It might be a better idea to use some other SQLite3 driver for Matlab, e.g., https://github.com/kyamagu/matlab-sqlite3-driver, http://jaewon.mine.nu/jaewon/2015/06/17/another-sqlite-interface-for-matlab/.
I'm using Integration Services to load data from an Excel file to SQL Server table. When I try to send a number stored as double (DT_R8) into a database column where data are stored as varchar(50) I find a queer rounding.
For example consider data in first row first column of above image. Original value is 31.35 but as a string it's stored as shown below
I already tried to use a Delivered Column transformation to cast to string before exporting to SQL, I also added a Round(x, 5) but I get the same result.
How can I solve this problem given that I can't change SQL column data type?
The only working solution was changing the input type from double (DT_R8) to currency [DT_CY]. It seems that the rounding performed on double (DT_R8) make its use difficult when parsing is somehow involved in the export process.
can somebody give me an example how to insert binary std::string using ODBC and C++ into BLOB column, please?
EDIT:
Duplicate of How to INSERT binary std::string into BLOB (MySQL).
If it is really a binary string, and you have actual binary data in it (e.g. embedded nulls) then you need to be careful not to use any of the std::string members that can treat it as a C string (e.g. with a terminating null) as you will obviously end up losing data.
The std::string class is not really appropriate for this purpose - it is written on the assumption that what you are working with is actually a string of characters - since you are using a blob or array of binary data, a std::vector is probably more appropriate.
To insert the data will require you to bind the content of the vector to the SQL query using bind parameters. That is to say, instead of using SQLExecDirect to execute a string containing the SQL query, you should use SQLPrepare to create the statement handle - you leave the spot where the value of the binary value would go with a '?', then use SQLBindParameter to bind the placeholder to the binary value. You then call the function using SQLExecute.
There are some code examples in the SQLBindParameter documentation above.