I want to drop a column called id which is an auto incrementing PK.
The SQL:
alter table "CO88GT"."XGLCTL" drop column id cascade;
And I get:
Error: [SQL0952] Processing of the SQL statement ended. Reason code 10.
SQLState: 57014
ErrorCode: -952
I could be wrong but I think it has something to do with preventing the table from losing data. To get around this issue I need to create a new table without the column and copy the data from the old table into the new table and then replace the old table with the new table.
Info
AS400 is giving you a warning (inquiry message) because of possible data loss, asking you to Cancel or Ignore the requested operation. So, beacuse of this being a interactive request, over JDBC/ODBC you cannot type 'I' to ignore, and AS throws you an ErrorCode: -952 with SQLState: 57014 and Reason code 10.
In the documentation of SQL0952 says:
Message Text: Processing of the SQL statement ended. Reason code &1.
Cause Text: The SQL operation was ended before normal completion. The reason code is &1. Reason codes and their meanings are:
* 1 - An SQLCancel API request has been processed, for example from ODBC.
* 2 - SQL processing was ended by sending an exception.
* 3 - Abnormal termination.
* 4 - Activation group termination.
* 5 - Reclaim activation group or reclaim resources.
* 6 - Process termination.
* 7 - An EXIT function was called.
* 8 - Unhandled exception.
* 9 - A Long Jump was processed.
* 10 - A cancel reply to an inquiry message was received.
* 11 - Open Database File Exit Program (QIBM_QDB_OPEN).
* 0 - Unknown cause.
If you are using JDBC and the SQL error isn't self-explanatory, you can make a JDBC connection with parameter 'errors=full', which will give much more info on the error. For other connection parameters see this.
example connection string:
jdbc:as400://serverName;libraries=*libl;naming=system;errors=full;
With that connection the resulting error would be like this:
Error: [SQL0952] Processing of the SQL statement ended. Reason code 10.
Cause . . . . . : The SQL operation was ended before normal completion.
The reason code is 10.
Reason codes and their meanings are:
1 -- An SQLCancel API request has been processed, for example from ODBC.
2 -- SQL processing was ended by sending an exception.
3 -- Abnormal termination.
4 -- Activation group termination.
5 -- Reclaim activation group or reclaim resources.
6 -- Process termination.
7 -- An EXIT function was called.
8 -- Unhandled exception.
9 -- A Long Jump was processed.
10 -- A cancel reply to an inquiry message was received.
11 -- Open Database File Exit Program (QIBM_QDB_OPEN).
0 -- Unknown cause.
Recovery . . . : If the reason code is 1, a client request was made to cancel SQL processing. For all other reason codes, see previous messages to determine why SQL processing was ended.
SQLState: 57014
ErrorCode: -952
The solution
So finally, if you cannot use STRSQL, another solution is to use iSeries Navigator, to be exact its "Run SQL scripts" (it is usually here --> "%Program Files%\IBM\Client Access\Shared\cwbundbs.exe").
But first of all you have to add a system reply parameter (only once per machine)
ADDRPYLE SEQNBR(1500) MSGID(CPA32B2) RPY('I')
This is done in "green screen". This sets a deafult answer ('I') on CPA32B2 inquiry message. The CPA32B2 is an internal massage id, which is tied to an drop column operation.
(It actually doesn't have to be done in "green screen", use it like CHGJOB command. Example :
cl: ADDRPYLE SEQNBR(1500) MSGID(CPA32B2) RPY('I');
)
Now you can start "Run SQL scripts", the first command to run is:
cl: CHGJOB INQMSGRPY(*SYSRPYL);
this changes the current job parameter INQMSGRPY, to *SYSRPYL. *SYSRPYL causes to look if exists a system reply parameter when an inquiry message should be displayed.
Now you can run your alter which drops the column.
Unfortunately, I don't know how to drop a column, just using JDBC. If someone knows please let me know.
References:
Understanding What Controls the Automatic Reply Function
Replying to Run-Time Inquiry Messages
Error in dropping column (forum post)
How can I avoid SQL0952 on ALTER TABLE?
Finally I found a solution:
CALL QSYS2.QCMDEXC('ADDRPYLE SEQNBR(1500) MSGID(CPA32B2) RPY(''I'')');
CALL QSYS2.QCMDEXC('CHGJOB INQMSGRPY(*SYSRPYL)');
ALTER TABLE <tablename> DROP COLUMN <column_name>;
There isn't enough information in your error message to be sure, but dropping a primary key column is generally quite risky and the database correctly makes it difficult.
You likely have a foreign key constraint involving that column.
Don't drop the constraint and delete that column unless you're sure you know what you're doing.
According to this post: http://bytes.com/topic/db2/answers/185467-drop-column-table
It is possible to drop a column using STRSQL in the green screen environment. I have access to this and it does work, but a client with a 400 does not have the licensed program to use STRSQL. The issue is that STRSQL will prompt if this is something I really want to do.
To get at the data I'm using SQuirrel SQL client with the JT400 JDBC driver... So I guess with the system insisting on prompting (and actually no way of getting the prompt even without STRSQL) it won't let me do it.
So I guess I'm stuck doing what I'm doing... creating a new table and copying the data and then swapping the tables.
The only way I found to get jdbc to work is to first manually change the default for this message. Then run your update application. In our case we use Liquibase. I could get the java's CommandCall to call ADDRPYLE and CHGJOB INQMSGRPY(*SYSRPYL), but it never actually allowed the alter table * drop column * to not give the follow error:
Error:
10 -- A cancel reply to an inquiry message was received.
Working Command:
CHGMSGD MSGID(CPA32B2) MSGF(QSYS/QCPFMSG) DFT('I')
Reference:
http://knowledgebase.progress.com/articles/Article/9678
green screen -- STRSQL will give you error msg to answer
alter table devlibsc/trklst drop column "ST"
Change of file TRKLST may cause data to be lost. (C I)
Related
I run into a Cannot enlarge string buffer message on my running postgREST API. I guess some tables are too large to work successful with the API.
I am using the docker postgrest/postgrest container from https://hub.docker.com/r/postgrest/postgrest with the version PostgREST 5.1.0.
Everything is working as expected but if the tables size getting too large, I get following error message.
hint null
details "Cannot enlarge string buffer containing 1073741822 bytes by 1 more bytes."
code "54000"
message "out of memory"
I can't determine the threshold when it's working or not.
Is there a possibility to enlarge the string buffer in some config file or is this hardcoded?
Are there any limits from the table size working with the API. So far I couldn’t find any information in the docu.
=========== Update
The postgres logs give me following SQL query:
WITH pg_source AS (
SELECT "public"."n_osm_bawue_line".*
FROM "public"."n_osm_bawue_line"
)
SELECT null AS total_result_set,
pg_catalog.count(_postgrest_t) AS page_total,
array[]::text[] AS header,
coalesce(json_agg(_postgrest_t), '[]')::character varying AS body
FROM (
SELECT *
FROM pg_source
) _postgrest_t
I use following postgres version:
"PostgreSQL 11.1 (Debian 11.1-1.pgdg90+1) on x86_64-pc-linux-gnu, compiled by gcc (Debian 6.3.0-18+deb9u1) 6.3.0 20170516, 64-bit"
Unless you recompile PostgreSQL is not possible to upgrade the limit(defined here).
My suggestion would be to try to reduce the size of the payload(are you sure you need all the data?) or get all of the payload in multiple requests.
With PostgREST you can do vertical filtering(just select the columns that you need) or paginate to reduce the number of rows you get in one request.
The error message comes from PostgreSQL. PostgREST just wraps the message in JSON and sends the HTTP response.
As a first step for finding the problem, look what is the exact HTTP request you do to trigger the error.
Then, enable PostgreSQL logging and repeat the request, check the logs and then you'll see what is the SQL query that causes this error. Run the query through pgAdmin or psql to make sure you got the problematic query.
Update your question with your findings. The SQL query would be what is needed to continue.
After that you could add a postgresql tag to your question.
There is always the possibility that the file being imported is either corrupted or malformed because of any number of reasons.
I just happened to have discovered in my case that my file had something like incorrect line endings (long story, unnecessary here) which caused the whole file to appear as one line, thus causing the obvious result. You may have something similar in your case that requires a find+replace kind of solution.
For whatever benefit to anyone else, I used this to resolve it:
tr -d '\0' < bad_file.csv > bad_file.csv.fixed
I have several counters in an application I am building, as am trying to get them to be dynamically created by the application as required.
For a simplistic example, if someone types a word into a script it should return the number of times that word has been entered previously. Here is an example of sql that may be executed if they typed the word example.
CREATE SEQUENCE IF NOT EXISTS example START WITH 1;
SELECT nextval('example')
This would return 1 the first time it ran, 2 the second time, etc.
The problem is when 2 people click the button at the same time.
First, please note that a lot more is happening in my application than just these statements, so the chances of them overlapping is much more significant than it would be if this was all that was happening.
1> BEGIN;
2> BEGIN;
1> CREATE SEQUENCE IF NOT EXISTS example START WITH 1;
2> CREATE SEQUENCE IF NOT EXISTS example START WITH 1; -- is blocked by previous statement
1> SELECT nextval('example') -- returns 1 to user.
1> COMMIT; -- unblocks second connection
2> ERROR: duplicate key value violates unique constraint
"pg_type_typname_nsp_index"
DETAIL: Key (typname, typnamespace)=(example, 109649) already exists.
I was under the impression that by using "IF NOT EXISTS", the statement should just be a no-op if it does exist, but it seems to have this race condition where that is not the case. I say race condition because if these two are not executed at the same time, it works as one would expect.
I have noticed that IF NOT EXISTS is fairly new to postgres, so maybe they haven't worked out all of the kinks yet?
EDIT:
The main reason we were considering doing things this way was to avoid excess locking. The thought being that if two people were to increment at the same time, using a sequence would mean that neither user should have to wait for the other (except, as in this example, for the initial creation of that sequence)
Sequences are part of the database schema. If you find yourself modifying the schema dynamically based on the data stored in the database, you are probably doing something wrong. This is especially true for sequences, which have special properties e.g. regarding their behavior with respect to transactions. Specifically, if you increment a sequence (with the help of nextval) in the middle of a transaction and then you rollback that transaction, the value of the sequence will not be rolled back. So most likely, this kind of behavior is something that you don't want with your data. In your example, imagine that a user tries to add word. This results in the corresponding sequence being incremented. Now imagine that the transaction does not complete for reason (e.g. maybe the computer crashes) and it gets rolled back. You would end up with the word not being added to the database but with the sequence being incremented.
For the particular example that you mentioned, there is an easy solution; create an ordinary table to store all the "sequences". Something like that would do it:
CREATE TABLE word_frequency (
word text NOT NULL UNIQUE,
frequency integer NOT NULL
);
Now I understand that this is just an example, but if this approach doesn't work for your actual use case, let us know and we can adjust it to your needs.
Edit: Here's how you the above solution works. If a new word is added, run the following query ("UPSERT" syntax in postgres 9.5+ only):
INSERT INTO word_frequency(word,frequency)
VALUES ('foo',1)
ON CONFLICT (word)
DO UPDATE
SET frequency = word_frequency.frequency + excluded.frequency
RETURNING frequency;
This query will insert a new word in word_frequency with frequency 1, or if the word exists already it will increment the existing frequency by 1. Now what happens if two transaction try to do that at the same time? Consider the following scenario:
client 1 client 2
-------- --------
BEGIN
BEGIN
UPSERT ('foo',1)
UPSERT ('foo',1) <====
COMMIT
COMMIT
What will happen is that as soon as client 2 tries increment the frequency for foo (marked with the arrow above), that operation will block because the row was modified by a different transaction. When client 1 commits, client 2 will get unblocked and continue without any errors. This is exactly how we wanted it to work. Also note, that postgresql will use row-level locking to implement this behavior, so other insertions will not be blocked.
EDIT: The main reason we were considering doing things this way was to
avoid excess locking. The thought being that if two people were to
increment at the same time, using a sequence would mean that neither
user should have to wait for the other (except, as in this example,
for the initial creation of that sequence)
It sounds like you're optimizing for a problem that likely does not exist. Sure, if you have 100,000 simultaneous users that are only inserting rows (since a sequence will only be used then normally) there is the possibility of some contention with the sequence but realistically there will be other bottle necks long before the sequence gets in the way.
I'd advise you to first prove that the sequence is an issue. With a proper database design (which dynamic DDL is not) the sequence will not be the bottle neck.
As a reference, DDL is not transaction safe in most databases.
Was trying to refresh a database which failed when dropping the AQ table 'SYSTEM.DEF$_AQCALL' with this error.
//------------
1. SqlBRuntimeException: Dropping Tables failed after 6/179 items (1 errors)
2. SqlBException: Fatal error executing resource: clean\tables\def$_aqcall
3. QueryException: Error executing resource (delimiter = '/'): clean\tables\def$_aqcall
4. QueryException: Error executing SQL statement (errcode=24005, sqlstate=99999: ORA-24005: Inappropriate utilities used to perform DDL on AQ table SYSTEM.DEF$_AQCALL):
DROP TABLE def$_aqcall CASCADE CONSTRAINTS
5. SQLException: errorcode=24005, sqlstate=99999, line=-1: ORA-24005: Inappropriate utilities used to perform DDL on AQ table SYSTEM.DEF$_AQCALL
//------------
Then tried manually stopping the queue and dropping the queue table even with the 'Force' option, but no luck.
When stopping the queue this is the error I'm getting.
//---------------------------
Error starting at line 5 in command:
BEGIN
DBMS_AQADM.STOP_QUEUE(
queue_name => 'SYSTEM.DEF$_AQCALL');
END;
Error report:
ORA-04063: package body "SYS.DBMS_AQADM_SYS" has errors
ORA-06508: PL/SQL: could not find program unit being called: "SYS.DBMS_AQADM_SYS"
ORA-06512: at "SYS.DBMS_AQADM", line 464
ORA-06512: at line 2
04063. 00000 - "%s has errors"
*Cause: Attempt to execute a stored procedure or use a view that has
errors. For stored procedures, the problem could be syntax errors
or references to other, non-existent procedures. For views,
the problem could be a reference in the view's defining query to
a non-existent table.
Can also be a table which has references to non-existent or
inaccessible types.
*Action: Fix the errors and/or create referenced objects as necessary.
//--------
Checking on the 'DBMS_AQADM_SYS' package using;
select owner,object_name,object_type,status from dba_objects where object_name='DBMS_AQADM_SYS';
shows that the Status of the 'Package Body' is 'INVALID' and I assume that this could be the cause of the above error.
Next step was to recompile this package to fix any issues in the package.
I recompiled the package as SYSDBA;
EXECUTE UTL_RECOMP.RECOMP_SERIAL();
as per http://docs.oracle.com/cd/B19306_01/appdev.102/b14258/u_recomp.htm#i1000051
This completed without any errors, but still the Status of the Package Body is 'Invalid'.
Tried using
sqlplus / as sysdba #?/rdbms/admin/utlrp
as per DBMS_METADATA and other packages invalid but still no luck.
Checked few forums and everyone suggests to recompile the package.
Appreciate if you have any insight on this issue.
Thanks.
Here are some ideas, in the order I would attempt them:
Try to figure out why it's invalid. If you're lucky the error message will give you a clue: select * from dba_errors where name = 'DBMS_AQADM_SYS';
Look for other invalid objects that might cause the problem: select * from dba_objects where status <> 'VALID';
Run utlrp multiple times. (That's an official Oracle recommendation in some processes; do the same thing multiple times.)
Manually recompile objects like this: alter package sys.dbms_aqadm_sys compile;. Recompiling objects may invalidate others, you may need to manually recompile them in a specific order.
Talk to your DBAs and find out if there was any recent maintenance on the servers lately. The only time I've had to do step #4 was after an upgrade.
Contact Oracle support.
I have read and read over MSDN, etc. Ok, so it signals the end of a batch.
What defines a batch? I don't see why I need go when I'm pasting in a bunch of scripts to be run all at the same time.
I've never understood GO. Can anyone explain this better and when I need to use it (after how many or what type of transactions)?
For example why would I need GO after each update here:
UPDATE [Country]
SET [CountryCode] = 'IL'
WHERE code = 'IL'
GO
UPDATE [Country]
SET [CountryCode] = 'PT'
WHERE code = 'PT'
GO is not properly a TSQL command.
Instead it's a command to the specific client program which connects to an SQL server (Sybase or Microsoft's - not sure about what Oracle does), signalling to the client program that the set of commands that were input into it up till the "go" need to be sent to the server to be executed.
Why/when do you need it?
GO in MS SQL server has a "count" parameter - so you can use it as a "repeat N times" shortcut.
Extremely large updates might fill up the SQL server's log. To avoid that, they might need to be separated into smaller batches via go.
In your example, if updating for a set of country codes has such a volume that it will run out of log space, the solution is to separate each country code into a separate transaction - which can be done by separating them on the client with go.
Some SQL statements MUST be separated by GO from the following ones in order to work.
For example, you can't drop a table and re-create the same-named table in a single transaction, at least in Sybase (ditto for creating procedures/triggers):
> drop table tempdb.guest.x1
> create table tempdb.guest.x1 (a int)
> go
Msg 2714, Level 16, State 1
Server 'SYBDEV', Line 2
There is already an object named 'x1' in the database.
> drop table tempdb.guest.x1
> go
> create table tempdb.guest.x1 (a int)
> go
>
GO is not a statement, it's a batch separator.
The blocks separated by GO are sent by the client to the server for processing and the client waits for their results.
For instance, if you write
DELETE FROM a
DELETE FROM b
DELETE FROM c
, this will be sent to the server as a single 3-line query.
If you write
DELETE FROM a
GO
DELETE FROM b
GO
DELETE FROM c
, this will be sent to the server as 3 one-line queries.
GO itself does not go to the server (no pun intended). It's a pure client-side reserved word and is only recognized by SSMS and osql.
If you will use a custom query tool to send it over the connection, the server won't even recognize it and issue an error.
Many command need to be in their own batch, like CREATE PROCEDURE
Or, if you add a column to a table, then it should be in its own batch.
If you try to SELECT the new column in the same batch it fails because at parse/compile time the column does not exist.
GO is used by the SQL tools to work this out from one script: it is not a SQL keyword and is not recognised by the engine.
These are 2 concrete examples of day to day usage of batches.
Edit: In your example, you don't need GO...
Edit 2, example. You can't drop, create and permission in one batch... not least, where is the end of the stored procedure?
IF OBJECT_ID ('dbo.uspDoStuff') IS NOT NULL
DROP PROCEDURE dbo.uspDoStuff
GO
CREATE PROCEDURE dbo.uspDoStuff
AS
SELECT Something From ATable
GO
GRANT EXECUTE ON dbo.uspDoStuff TO RoleSomeOne
GO
Sometimes there is a need to execute the same command or set of commands over and over again. This may be to insert or update test data or it may be to put a load on your server for performance testing. Whatever the need the easiest way to do this is to setup a while loop and execute your code, but in SQL 2005 there is an even easier way to do this.
Let's say you want to create a test table and load it with 1000 records. You could issue the following command and it will run the same command 1000 times:
CREATE TABLE dbo.TEST (ID INT IDENTITY (1,1), ROWID uniqueidentifier)
GO
INSERT INTO dbo.TEST (ROWID) VALUES (NEWID())
GO 1000
source:
http://www.mssqltips.com/tip.asp?tip=1216
Other than that it marks the "end" of an SQL block (e.g. in a stored procedure)... Meaning you're on a "clean" state again... e.G: Parameters used in the statement before the code are reset (not defined anymore)
As everyone already said, "GO" is not part of T-SQL. "GO" is a batch separator in SSMS, a client application used to submit queries to the database. This means that declared variables and table variables will not persist from code before the "GO" to code following it.
In fact, GO is simply the default word used by SSMS. This can be changed in the options if you want. For a bit of fun, change the option on someone else's system to use "SELECT" as a batch seperator instead of "GO". Forgive my cruel chuckle.
It is used to split logical blocks. Your code is interpreted into sql command line and this indicate next block of code.
But it could be used as recursive statement with specific number.
Try:
exec sp_who2
go 2
Some statement have to be delimited by GO:
use DB
create view thisViewCreationWillFail
Here’s the scenario:
You load a page, which renders based on the data in the database (call these the “assumptions”)
Someone changes the assumptions
You submit your page
ERROR!
The general pattern to solve this problem is this (right?):
In your save proc, inside a begin and commit transaction, you validate your assumptions first. If any of them changed, you should return a graceful error message, something like an XML list of the ID’s you had problems with, that you handle in the page rather than let it be handled by the default error handling infrastructure.
So my question is what is the best way to do that?
Return the xml list and an error flag in out parameters that are unset and 0 if it completes correctly?
Use an out parameter to return an error status, and the result of the proc be either the error list or the valid results of the proc?
Something else? (I should note that raiseerror would cause the proc to be in error, and get picked up by the default error handling code)
Update: I would like to return a maniplatable list of IDs that failed (I plan to highlight those cells in the application). I could return them in CSV format in RAISEERROR, but that seems dirty.
I agree - I like RAISEERROR:
-- Validate #whatever
IF #whatever >= '5'
BEGIN
RAISERROR ('Invalid value for #whatever - expected a value less than 5, but received %s.', 10, 1, #whatever)
RETURN 50000
END;
Use the RAISERROR function with the appropriate severity and/or wait level. If you use a low severity this does not necessarily cause an exception, as you contend, and with .Net at least its pretty simple to retrieve these messages. The only downside is that with the StoredProcedure command type in .Net messages are only pumped in groups of 50.
Stored procedures can return multiple result sets. Based on your update, you could also insert errored ids into a temporary table, and then at the end of your procedure select the records from that table as an additional result set you can look at.
I would do an output parameter with a message, the return will already have something which is not 0 if there is an error
also be careful with doomed transaction and check with xact_error, see Use XACT_ABORT to roll back non trapable error transactions