I have a column in my oracle table with CLOB datatype.
How do I store .txt file in this column and how can I retrieve the same file?
Below is the table definition
fileID Number
logFile CLOB
Thanks in advance
Loading a file into a CLOB in PL/SQL is pretty easy-- you just need to use the DBMS_LOB.LoadCLOBFromFile procedure
CREATE DIRECTORY file_dir
AS <<path on database server file system>>;
GRANT read, write
ON file_dir
TO your_user_name;
DECLARE
l_src_file bfile := BFileName( 'FILE_DIR', <<name of file>> );
l_dest_lob clob;
l_dest_offset integer := 1;
l_src_offset integer := 1;
l_lang_context number := dbms_lob.default_lang_ctx;
l_warning number;
BEGIN
dbms_lob.open( l_src_file, dbms_lob.lob_readonly );
INSERT INTO some_table( fileID, logFile )
VALUES( fileIDSeq.nextval, empty_clob() )
RETURNING logFile
INTO l_dest_lob;
dbms_lob.LoadCLOBFromFile(
dest_lob => l_dest_lob,
src_bfile => l_src_file,
amount => dbms_lob.getLength( l_src_file ),
dest_offset => l_dest_offset,
src_offset => l_src_offset,
bfile_csid => dbms_lob.default_csid,
lang_context => l_lang_context,
warning => l_warning );
dbms_lob.close( l_src_file );
END;
/
Writing the file from the CLOB to the file system again is a bit more involved. I would use something like Tom Kyte's clob_to_file procedure
Related
BLOB to CLOB Conversion : Cyrillic characters are not getting converted properly
Based on our product migration, I have an requirement to replace below mentioned single byte character to Double byte character in each and every record but the respective column is BLOB datatype encoded with AL32UTF8 so I'm using the below procedure to convert column from BLOB to CLOB and replace the single byte character to Double byte character and convert back to CLOB to BLOB.
NLS_CHAR--> AL32UTF8
For ex:
when I tried with CL8ISO8859P5 character set in CLOB conversion function, Bulgarian data is corrupted and If I tried with AL32UTF8 character set then the respective Cyrillic character got corrupted.
select convert_to_clob(XMLRECORD) From F_TEC_OUTPUT_T
CLOB conversion with AL32UTF8 characterset:
ONE�АНУЛИРАНЕ НА ОПРОСТЕНА ФАКТУРА_�THREE
CLOB conversion with CL8ISO8859P5 characterset:
ONEўаааЃааа ааа аа ааа ааЁаЂааа аЄаааЂаЃа а_ўTHREE
select recid, dbms_lob.substr(XMLRECORD) as raw_xrec
from F_TEC_OUTPUT_T
[enter image description here][1]
Please suggest the proper way to convert this.
Single byte ---> Double byte
ў --> яЃО
§ --> яЃН
ќ --> яЃМ
In RAW:
FE --> EFA3BE
FD --> EFA3BD
FC --> EFA3BC
FB --> EFA3BB
l_clob CLOB;
l_dest_offset NUMBER := 1;
l_src_offset NUMBER := 1;
l_lang_context NUMBER := dbms_lob.default_lang_ctx;
l_warning NUMBER;
BEGIN
dbms_lob.createtemporary(l_clob, TRUE);
dbms_lob.converttoclob(dest_lob => l_clob,
src_blob => l_blob,
amount => dbms_lob.lobmaxsize,
dest_offset => l_dest_offset,
src_offset => l_src_offset,
blob_csid => nls_charset_id('CL8ISO8859P5'),
lang_context => l_lang_context,
warning => l_warning);
RETURN l_clob;
END convert_to_clob;
CREATE OR REPLACE FUNCTION convert_to_blob(l_clob CLOB) RETURN BLOB IS
l_blob BLOB;
l_dest_offset NUMBER := 1;
l_src_offset NUMBER := 1;
l_lang_context NUMBER := dbms_lob.default_lang_ctx;
l_warning NUMBER;
BEGIN
dbms_lob.createtemporary(l_blob, TRUE);
dbms_lob.converttoblob(dest_lob => l_blob,
src_clob => l_clob,
amount => dbms_lob.lobmaxsize,
dest_offset => l_dest_offset,
src_offset => l_src_offset,
blob_csid => nls_charset_id('AL32UTF8'),
lang_context => l_lang_context,
warning => l_warning);
RETURN l_blob;
END convert_to_blob;
CREATE OR REPLACE PROCEDURE convert_blob_file(p_tname in varchar2,parallel_no_cnt in number default 1,record_cmt_cnt in number default 1) IS
TYPE cur_typ IS REF CURSOR;
getcursordata cur_typ;
ConversionRecID VARCHAR2(2000);
BinaryValueSource BLOB;
BinaryValueDest BLOB;
BinaryValueTemp CLOB;
cnt NUMBER := 1;
Dicttablename VARCHAR2(2000);
Marker_R_count NUMBER := 0;
XmlrecordTemp CLOB;
Selectstring VARCHAR2(2000);
select_table_query VARCHAR2(1000):= 'SELECT /*+ PARALLEL('''||parallel_no_cnt||''') */ RECID,XMLRECORD FROM ' || p_tname || ' WHERE XMLRECORD IS NOT NULL';
BEGIN
OPEN getcursordata FOR select_table_query;
LOOP
FETCH getcursordata INTO ConversionRecID, BinaryValueSource;
EXIT WHEN getcursordata%NOTFOUND;
BinaryValueTemp := convert_to_clob(BinaryValueSource);
BinaryValueTemp := REPLACE(BinaryValueTemp,CHR(53662),CHR(15705022)); -- #FM Separator
BinaryValueTemp := REPLACE(BinaryValueTemp,CHR(49831),CHR(15705021)); -- #VM Separator
BinaryValueTemp := REPLACE(BinaryValueTemp,CHR(53660),CHR(15705020)); -- #SM Separator
BinaryValueTemp := REPLACE(BinaryValueTemp,CHR(53659),CHR(15705019)); -- #TM Separator
BinaryValueDest := convert_to_blob(BinaryValueTemp);
EXECUTE IMMEDIATE 'UPDATE /*+ PARALLEL('''||parallel_no_cnt||''') */'||p_tname||' SET XMLRECORD = :v1 WHERE RECID= :v2' USING BinaryValueDest,ConversionRecID;
IF cnt=record_cmt_cnt THEN
cnt:=1;
COMMIT;
ELSE
cnt := cnt + 1;
END IF;
END LOOP;
CLOSE getcursordata;
DBMS_OUTPUT.PUT_LINE('Time------'||to_char(sysdate, 'HH24:MI:SS'));
END;```
[1]: https://i.stack.imgur.com/t9w19.jpg
How do you check if the queue table exist before flushing it.
I have used the below syntax to create queue table
CREATE type Message_typ as object (
subject VARCHAR2(30),
text VARCHAR2(80));
BEGIN
dbms_aqadm.CREATE_QUEUE_TABLE (
queue_table => 'XX'
,queue_payload_type => 'Message_typ'
);
END;
And the below code to purge the flush table:
declare
l_type dbms_aqadm.aq$_purge_options_t;
begin
l_type.block := true;
l_type.delivery_mode := dbms_aq.buffered;
dbms_aqadm.purge_queue_table(queue_table => 'XX',
purge_condition => '',
purge_options => l_type);
l_type.block := true;
l_type.delivery_mode := dbms_aq.persistent;
dbms_aqadm.purge_queue_table(queue_table => 'XX',
purge_condition => '',
purge_options => l_type);
end;
Please guide how to check if the queue table exists and if exists do a purge.
Thanks.
I have a procedure where I am checking whether there are new codes. If there are then insert them into a table. And also save the new data into a csv or txt file and email them to me.
I can't get the logic for how to redirect the new data to file or just even put the data as simple text in the email. Thanks
create or replace
PROCEDURE new_codes_test( today_date IN VARCHAR2 DEFAULT NULL, v_proc_return OUT NUMBER) AS
sql_str VARCHAR2(4000);
.....
BEGIN
v_start_time := SYSDATE;
v_proc_return := 0;
....
INSERT INTO NEW_CODES_test
SELECT DISTINCT Sy_ID ,P_CODE, SYSDATE
FROM X.B
WHERE NOT EXISTS (SELECT DISTINCT Sy_ID, P_CODE
FROM X.C
WHERE today = today_date) ;
COMMIT;
--SELECT ___ into ___ from X.B;
sql_str := 'UTL_MAIL.send(sender => ''
,recipients => ''
,cc => ''
,subject => 'New codes'
,MESSAGE => '' )';
--EXECUTE IMMEDIATE sql_str;
p_proc_return := v_proc_return;
EXCEPTIONS
....
END;
To write to a file the UTL_FILE package will come in handy. To write an email you'll need to put the text to be sent into some sort of string before passing it to the MESSAGE argument of UTL_MAIL.SEND. You'll also need to be sure UTL_MAIL is installed and set up on your server; see this FAQ.
So something like the following may be useful:
CREATE OR REPLACE FUNCTION NEW_CODES_TEST(today_date IN VARCHAR2)
RETURN NUMBER
AS
strMessage VARCHAR2(32767);
nRows NUMBER := 0;
fHandle UTL_FILE.FILE_TYPE;
BEGIN
v_start_time := SYSDATE;
fHandle := UTL_FILE.FOPEN(someDirectory, someFilename, 'w');
FOR aRow IN (SELECT DISTINCT SY_ID ,P_CODE
FROM X.B
WHERE NOT EXISTS (SELECT DISTINCT Sy_ID, P_CODE
FROM X.C
WHERE today = today_date)
LOOP
INSERT INTO NEW_CODES_test
VALUES (aRow.SY_ID, aRow.P_CODE, SYSDATE);
UTL_FILE.PUT_LINE(fHandle, aRow.SY_ID || ', ' || aRow.P_CODE);
strMessage := strMessage || 'Added ' || aRow.SY_ID || ', ' ||
aRow.P_CODE || CHR(10);
nRows := nRows + 1;
END LOOP;
COMMIT;
UTL_FILE.FCLOSE(fHandle);
UTL_MAIL.SEND(sender => 'me#mycompany.com',
recipients => 'you#someplaceelse.net',
subject => 'New codes',
message => strMessage);
RETURN 0;
EXCEPTIONS
WHEN OTHERS THEN
DBMS_OUTPUT.PUT_LINE('Error: ' || SQLERRM);
RETURN SQLCODE;
END NEW_CODES_TEST;
Share and enjoy.
I am teaching myself to use SQLite and FireDAC together in Delphi. I am not very experienced with the latest incarnations of databases and tools so after writing a very simple application to display a single table from an SQLite file, I decided that I would put together a simple viewer 'frame' that would help me learn and maybe give me (eventually) a debugging tool to put in my Application for engineering use.
So, I've used a simple TTreeView and I wish to populate it with a hierarchy of 'databases' (catalogues?), 'tables', 'field names' and 'field types'. So far it has been remarkably easy to list the catalogues, tables and fields (using TFDConnection.Getxxxxx) but I cant see how to go deeper to get field definitions. Is this possible to do from a TFDConnection? Or do I need to open a temporary query?
My existing code is shown below and my 'field types' would be a further nested loop when shown as '// xxxxxxxxxxxxxxxxxxx'
procedure TForm1.Button1Click(Sender: TObject);
procedure DatabaseToTreeView( AConnection : TFDConnection; ATreeView : TTreeView );
procedure ProcessConnection;
procedure ProcessCatalogueName( const ACatalogueName : string; ARoot : TTreeNode );
procedure ProcessTableName( const ATableName : string; ARoot : TTreeNode );
var
List : TStrings;
{Node : TTreeNode;}
I : integer;
begin
List := TStringList.Create;
try
AConnection.GetFieldNames( ACatalogueName, '', ATableName, '', List );
for I := 0 to List.Count-1 do
begin
{Node := }ATreeView.Items.AddChild( ARoot, List[I] );
// xxxxxxxxxxxxxxxxxxx
end;
finally
List.Free;
end;
end;
var
List : TStrings;
Node : TTreeNode;
I : integer;
begin
List := TStringList.Create;
try
AConnection.GetTableNames( ACatalogueName, '', '', List );
for I := 0 to List.Count-1 do
begin
Node := ATreeView.Items.AddChild( ARoot, List[I] );
ProcessTableName( List[I], Node );
end;
finally
List.Free;
end;
end;
var
List : TStrings;
Node : TTreeNode;
I : integer;
begin
List := TStringList.Create;
try
AConnection.GetCatalogNames( '', List );
if List.Count = 0 then
ProcessCatalogueName( '', nil )
else
for I := 0 to List.Count-1 do
begin
Node := ATreeView.Items.AddChild( nil, List[I] );
ProcessCatalogueName( List[I], Node );
end;
finally
List.Free;
end;
end;
begin
ATreeView.Items.Clear;
ATreeView.Items.BeginUpdate;
try
ProcessConnection;
finally
ATreeView.Items.EndUpdate;
end;
end;
begin
FDConnection1.Open;
FDQuery1.Active := true;
DatabaseToTreeView( FDConnection1, TreeView1 );
end;
Many thanks, Brian.
One solution is to instantiate a TFDTable, connect it to AConnection and call FieldDefs.Update. This won't fetch any data.
Use the TFDMetaInfoQuery component. It is unified for getting metadata information, so it's usable with any kind of supported DBMS. It populates metadata resultsets by the requested MetaInfoKind and given DBMS object description.
Instead of using a temporary query with a false condition to get table schema without any data (such as "select * from tablename where 1=0" - I assume that is what you meant), depending on your database, you could also use a query to get table information. Like;
For MySQL:
show columns from tablename;
For SQLite:
PRAGMA table_info(tablename)
For MS SQL Server:
select column_name, data_type, character_maximum_length from INFORMATION_SCHEMA.COLUMNS where table_name = 'tablename';
I believe PostgreSQL also has such a function, however I dont have a pgsql installation handy at this time.
I'm trying to create a queue and a callback that triggers when a message is queued, but I can't get the callback to trigger. What am I doing wrong?
I have a trigger that enqueues a message, and I can see it on the queue message table, and I can dequeue it by hand and process it, I just can't get the callback to fire on enqueue.
BEGIN
DBMS_AQADM.CREATE_QUEUE_TABLE (
queue_table => 'queue_message_table',
queue_payload_type => 'queue_message_type',
multiple_consumers => TRUE);
DBMS_AQADM.CREATE_QUEUE (
queue_name => 'message_queue',
queue_table => 'queue_message_table');
DBMS_AQADM.START_QUEUE (queue_name => 'message_queue');
END;
CREATE OR REPLACE PROCEDURE queue_callback(
context RAW, reginfo SYS.AQ$_REG_INFO, descr SYS.AQ$_DESCRIPTOR, payload RAW, payloadl NUMBER) AS
queue_options DBMS_AQ.DEQUEUE_OPTIONS_T;
message_properties DBMS_AQ.MESSAGE_PROPERTIES_T;
my_message queue_message_type;
ret varchar2(200);
message_id RAW(16);
BEGIN
DBMS_OUTPUT.PUT_LINE('Callback');
queue_options.msgid := descr.msg_id;
queue_options.consumer_name := descr.consumer_name;
DBMS_AQ.DEQUEUE(
queue_name => descr.queue_name,
dequeue_options => queue_options,
message_properties => message_properties,
payload => my_message,
msgid => message_id );
ret := handle_message(my_message);
commit;
END;
BEGIN
DBMS_AQADM.ADD_SUBSCRIBER (queue_name => 'message_queue',
subscriber => SYS.AQ$_AGENT('queue_subscriber', 'message_queue',NULL));
DBMS_AQ.REGISTER (
SYS.AQ$_REG_INFO_LIST(
SYS.AQ$_REG_INFO(
'MESSAGE_QUEUE:QUEUE_SUBSCRIBER',
DBMS_AQ.NAMESPACE_AQ,
'plsql://QUEUE_CALLBACK',
HEXTORAW('FF')
)
), 1
);
END;
At first glance, it appears you're neither starting the queue (dbms_aqadm.start_queue), neither are you enqueueing anything to it (dbms_aq.enqueue).
I'd recommend following this demo.
You need to be careful with the database version. some bugs has been reported about issues with Oracle Aq.
In particular I've followed this link to built my own sample, executing the demo in a Oracle 11gR2 enterprise database. I was abled to enqueue, dequeue, purge the queue but the listener created with Dbms_Aq.Register didn't work.
I ran the same example downloading a Oracle 11g R2 xe database and it worked.
The same example was runned in a Oracle 10gR2 instance and it works perfectly.
There are some things that you need to be careful on using aq:
use the appropriate parameters adding the subscriber
use the appropriate namespace registering the listener with Dbms_Aq.Register
use the multiple consumers flag declaring the queue table
use the appropriate permissions to packages and to handle the queues
use the qualified name of the queues in some cases if it didn't works.
'
First create the schema
connect / as sysdba
-- #?/rdbms/admin/dbmsaqad.sql --(install if you don't have aq installed yet)
-- create the user and permissions
create user aqadmin identified by aqadmin default tablespace users temporary tablespace temp;
GRANT create session TO aqadmin;
grant connect, resource to aqadmin;
GRANT aq_administrator_role TO aqadmin IDENTIFIED BY aqadmin;
GRANT execute ON dbms_aq TO aqadmin;
GRANT execute ON dbms_aqadm TO aqadmin;
Create the ddl objects
CREATE TABLE demo_queue_message_table
( message VARCHAR2(4000) );
Create the aq-objects
create or replace type demo_queue_payload_type as object(message varchar2(4000)) ;
/
begin
DBMS_AQADM.CREATE_QUEUE_TABLE (queue_table => 'demo_queue_table', queue_payload_type => 'demo_queue_payload_type',multiple_consumers => TRUE);
DBMS_AQADM.CREATE_QUEUE (queue_name => 'demo_queue', queue_table => 'demo_queue_table');
DBMS_AQADM.START_QUEUE('demo_queue');
end;
/
CREATE or replace PROCEDURE demo_queue_callback_procedure(
context RAW,
reginfo SYS.AQ$_REG_INFO,
descr SYS.AQ$_DESCRIPTOR,
payload RAW,
payloadl NUMBER
) AS
r_dequeue_options DBMS_AQ.DEQUEUE_OPTIONS_T;
r_message_properties DBMS_AQ.MESSAGE_PROPERTIES_T;
v_message_handle RAW(16);
o_payload demo_queue_payload_type;
BEGIN
r_dequeue_options.msgid := descr.msg_id;
r_dequeue_options.consumer_name := descr.consumer_name;
DBMS_AQ.DEQUEUE(
queue_name => descr.queue_name,
dequeue_options => r_dequeue_options,
message_properties => r_message_properties,
payload => o_payload,
msgid => v_message_handle
);
INSERT INTO demo_queue_message_table ( message )
VALUES ( 'Message [' || o_payload.message || '] ' ||
'dequeued at [' || TO_CHAR( SYSTIMESTAMP,
'DD-MON-YYYY HH24:MI:SS.FF3' ) || ']' );
COMMIT;
END;
/
BEGIN
DBMS_AQADM.ADD_SUBSCRIBER (
queue_name => 'demo_queue',
subscriber => SYS.AQ$_AGENT(
'demo_queue_subscriber',
NULL,
NULL )
);
DBMS_AQ.REGISTER (
SYS.AQ$_REG_INFO_LIST(
SYS.AQ$_REG_INFO(
'DEMO_QUEUE:DEMO_QUEUE_SUBSCRIBER',
DBMS_AQ.NAMESPACE_AQ,
'plsql://DEMO_QUEUE_CALLBACK_PROCEDURE',
HEXTORAW('FF')
)
),
1
);
END;
/
And finally test the queue
DECLARE
r_enqueue_options DBMS_AQ.ENQUEUE_OPTIONS_T;
r_message_properties DBMS_AQ.MESSAGE_PROPERTIES_T;
v_message_handle RAW(16);
o_payload demo_queue_payload_type;
BEGIN
o_payload := demo_queue_payload_type(
TO_CHAR(SYSTIMESTAMP, 'DD-MON-YYYY HH24:MI:SS.FF3' )
);
DBMS_AQ.ENQUEUE(
queue_name => 'demo_queue',
enqueue_options => r_enqueue_options,
message_properties => r_message_properties,
payload => o_payload,
msgid => v_message_handle
);
COMMIT;
END;
/