sybase sql anywhere 11 query results are incorrect - sql

I have the following table which has >13.000 rows.
CREATE TABLE "DBA"."mytable" (
"c1" numeric(8,0) NOT NULL,
"c2" numeric(2,0) NOT NULL,
"c3" numeric(4,0) NOT NULL,
"c4" numeric(8,0) NOT NULL,
PRIMARY KEY ("c1","c2","c3","c4")
)
The following query returns no rows when there are at least two rows that happen to meet the condition:
select * from mytable A where A.c1=229 and A.c3=1
More strangely, a slightly modified (but same) version of the query returns 2 rows as expected:
select * from mytable A where A.c1=229 and A.c3+1=2
Having suspected there is some physical corruption in the db, I have created a new db, created the table with the above code and loaded values from an unload file. The results are the same.
I know all four columns in PK is not good design, but this shouldn't be an excuse for the db to return wrong results.
By playing with the column creation order and dropping the PK the problem disappears and reappears.
Does aynbody know a fix or some workaround about this problem?
The DB is on a Windows 8 64-bit system, the locale is Turkish.
Thanks


I remember long ago in the times I used Sybase, that sometimes the table's data get silently corrupted.
The only solution we found was to re-create the table and insert the data again. I'm sorry but that was the only solution we found. So, you could copy the data to another table, then drop and recreate your table, and finally copy the data back.

Related

Why is my update statement not working in SQL Server Management Studio against my Azure Database?

I have written a very basic update statement that was working fine previously and now, for reasons unknown, no longer updates any data, despite not returning any errors.
I have two tables, NewCars and OldCars
New Cars
CarId INT [NONE NULLABLE]
Make VARCHAR [NULLABLE]
Model VARCHAR [NULLABLE]
Design INT [NULLABLE]
OldId INT [NONE NULLABLE]
Old Cars
CarId INT [NONE NULLABLE]
Make VARCHAR [NULLABLE]
Model VARCHAR [NULLABLE]
DesignId INT [NULLABLE]
I need to copy the 'Design' from the old table to the new one. Here is the query that I wrote that has worked with previous columns in this database.
UPDATE NewCars
SET Design = (SELECT DesignId FROM OldCars WHERE OldCars.CarId = NewCars.OldId)
When I run my statement, it completes with the message 'x Number of rows affected' x being the total record count. When I check the data, the column has nothing in it. I tried this same approach on other columns and it does the same thing.
I have tried restarting my Azure database which didn't change anything. I then tried to run a query to check if another query statement was perhaps still running, there seems to be nothing there. I've made sure the source and destination data types are the same as well.
Can anyone help me with what has gone wrong here?

I am not sure what you want to accopmplish with this update but this will work:
update NewCars
set Design = (select DesignId from OldCars WHERE OldCars.CarId = NewCars.CarId);
In your update statement you have NewCar.OldId and NewCars table does not have a OldId column(from your specifications). And also it is NewCars with s in the end. So please check the statement and give us the one with no errors and no updates...
If you want to update column NewCars.Design with a value from column OldCars.DesignId where the column NewCars.CarId matches column OldCars.OldId then the value in the column OldId can not appear more than one time. Else, you will have an error.

Thanks to VBoka for assiting with this, it turns out there were problems with the corrolation of the Id numbers as the column data was incorrect.

SQLiteexception database disk image is malformed

I have a weird error with a SQLite Database: You can download it here
Everytime I try to insert something in the Table "CurrencyTransactions" it fails because a new column called 7 appeared for no reason.
I tried to drop the table but
I ran PRAGMA integrity_check but I've this error then
Then I tried to export a .sql file and to import it again in a fresh new database but
1) If I import the structure only, it works fine and I don't have the 7 column anymore
2) If I import the entries then, it fails with this error:
It means something like: "Error in process #74: not an error"
To finish, I also tried this solution but the new database created is empty.
What can I do? I really need to save the entries.

What I suggest is in DB Browser.
File/Export/Database to SQL file.
Select All (for all tables)
Other options up to you other than Export Everything
Save the file.
Close the database.
Open a new database e.g nadekobotfix.db. (could be same name but different location)
Note 1-6 takes a minute or so (just under 60k).
Do the hard work according to :-
You may need to remove/ignore the first and last lines (BEGIN TRANSACTION; and the subsequent COMMIT;)
You would probably not be able to run the generated SQL directly due to constraints (tried this an failed with constraints).
You need to copy sections from the file and run according to the hierarchy as imposed by the constraints (foreign keys). If you have CHECK constraints these may need to be considered. (no Triggers to worry about).
Running SELECT * FROM sqlite_master WHERE type = 'table' AND instr(sql,'CHECK'); returns nothing so there are no CHECK constraints.
Indexes could/should be left till last (as they are in the generated SQL).
A section would consist of a table's create statement along with the insert statements.
You may wish to create a spreadsheet of the tables(sections) marking them off when they have been done.
The following query could assist as those with NA could be done first
SELECT CASE WHEN instr(sql,'FOREIGN KEY') THEN 'FK' ELSE 'NA' END AS fkey, name,sql
FROM sqlite_master
WHERE type = 'table' AND name NOT LIKE 'sqlite%' ORDER BY instr(sql,'FOREIGN KEY')
you could export individual tables from DB Browser for SQlite marking them off when done.
You may wish to do an integrity_check at regular intervals.
If this works (you might have to make adjustments to the SQL) then you can rename the old db and then rename the new (or move the old and the copy the new if using the same database name).
Note you may still have to determine how the corruption occurred.
You may wish to backup the database regularly.
You may wish to have a look at How To Corrupt An SQLite Database File
You may wish to heed :-
With few exceptions, analysis of a corrupt database does not normally
help to determine what went wrong. A better approach to avoiding
"danger", we have found, is to read and understand
https://www.sqlite.org/howtocorrupt.html
* in database main *
Page 10628: btreeInitPage() returns error code 11
This indicates that the page header is so badly corrupted that SQLite
cannot interpret this page at all. One possible reason: page 10628
has been zeroed. Can you look at a hex dump of that page? (Remember
that SQLite numbers pages beginning with 1, so the start of the page
is pgsz*10627 where pgsz is the page size.)
-- D. Richard Hipp
“btreeInitPage() returns error code 11”
Sample adjustment required
The Reminders table has a column called When, this is an SQL keyword (inadvisable column name IMO) so the generated SQL for the INSERT doesn't wrap the column name so you will get an error.
i.e. :-
CREATE TABLE IF NOT EXISTS `Reminders` (
`Id` INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
`ChannelId` INTEGER NOT NULL,
`IsPrivate` INTEGER NOT NULL,
`Message` TEXT,
`ServerId` INTEGER NOT NULL,
`UserId` INTEGER NOT NULL,
`When` TEXT NOT NULL,
`DateAdded` TEXT
);
INSERT INTO `Reminders` (Id,ChannelId,IsPrivate,Message,ServerId,UserId,When,DateAdded) VALUES (1270,367886754973351936,1,'Birthday Day',318127386367623170,367886754973351936,'2018-05-03 22:07:48.1860996','2018-03-18 22:07:48.186101'),
(1271,248278722656993281,1,'to remind Chanmi to remind Jayos to DeagleMomoka',318127386367623170,248278722656993281,'2018-05-05 22:08:58.4915565','2018-03-18 22:08:58.4915582'),
(1376,170240129414201344,1,'timely',318127386367623170,170240129414201344,'2018-03-29 09:00:29.4476776','2018-03-28 09:00:29.447679'),
(1377,373301201158144000,1,'timely',318127386367623170,373301201158144000,'2018-03-29 09:50:14.1631563','2018-03-28 09:50:14.1631577'),
(1378,248278722656993281,1,'timely',318127386367623170,248278722656993281,'2018-03-29 11:24:27.0250275','2018-03-28 11:24:27.025029'),
(1379,421433212716318721,1,'to timely',318127386367623170,421433212716318721,'2018-03-29 19:21:17.7465563','2018-03-28 19:21:17.7465584'),
(1380,346513954966863872,1,'t',318127386367623170,346513954966863872,'2018-03-29 19:42:23.4758798','2018-03-28 19:42:23.4758816'),
(1381,272735316002209792,1,'t!daily',318127386367623170,272735316002209792,'2018-03-29 21:01:47.5616218','2018-03-28 21:01:47.5616236'),
(1382,298272937243312132,1,'timely',318127386367623170,298272937243312132,'2018-03-29 23:18:02.8826873','2018-03-28 23:18:02.8826891'),
(1383,332340162774302720,1,'t',318127386367623170,332340162774302720,'2018-03-30 01:55:21.4704139','2018-03-29 01:55:21.4704156'),
(1384,367165474246754314,1,'tatyahaksodoeo',318127386367623170,367165474246754314,'2018-03-30 03:46:18.8805182','2018-03-29 03:46:18.8805196'),
(1385,290086674761908225,1,'timely',318127386367623170,290086674761908225,'2018-03-30 07:02:33.4115303','2018-03-29 07:02:33.4115321'),
(1386,168064128500367360,1,'timely',318127386367623170,168064128500367360,'2018-03-30 07:19:09.1915867','2018-03-29 07:19:09.1915885');
would have to be changed to use (square brackets, single or double quotes or grave accents can be used to enclose/wrap/quote the offending keyword):-
.......INSERT INTO `Reminders` (Id,ChannelId,IsPrivate,Message,ServerId,UserId,[When],DateAdded) ......
Likewise table SelfAssignableRoles has the GROUP keyword as a column name.
Likewise table Permissionv2 and table StartupCommand have the INDEX keyword as a column name.
Potential Issue
As an exercise I've tried doing the above and have managed to get 67 out of the 71 tables (66 out of 70 of your tables as sqlite_sequence is automatically created).
However, there appears to be an issue, between the Clubs table and the DiscordUser table. I believe that there is a circular reference between them. Thus as WaifuInfo and WaifuUpdates are reliant upon the DiscordUser table and as WaifuItem is realiant upon WaifInfo. The tables mentioned here have not been successfully copied.
A word of warning. If you attempt to create Clubs and or DiscordUser using the existing constraints you may end up in a situation where one always has to exist.
e.g. if DiscordUser exists but Clubs doesn't then
DROP TABLE IF EXISTS `DiscordUser`;
results in :-
no such table: main.Clubs: DROP TABLE IF EXISTS `DiscordUser`;
If you then create Clubs and try the DROP with a very basic (no Constraints) using :-
CREATE TABLE IF NOT EXISTS `Clubs` (ID INTEGER PRIMARY KEY);
DROP TABLE IF EXISTS `DiscordUser`;
The result is good as per :-
Query executed successfully: DROP TABLE IF EXISTS `DiscordUser`; (took 1ms)
Now try to DROP Clubs using :-
--CREATE TABLE IF NOT EXISTS `Clubs` (ID INTEGER PRIMARY KEY);
--DROP TABLE IF EXISTS `DiscordUser`;
DROP TABLE IF EXISTS `Clubs`;
and you can't as DiscordUser doesn't exist as per :-
no such table: main.DiscordUser: DROP TABLE IF EXISTS `Clubs`;
I've tried closing the database in case it was a caching issue but the behaviour remains.
As such, I'd strongly suggest having a good look at the constraint usage and being sure of correcting the issues before trying to copy all of the tables (I guess that there is a chance that this could be part of the cause of the corruption, however why/how is way beyond me).
P.S. The method I used was (1-6):-
Then for 7 :-
Run the sqlite_master query, from above, select all cells and copy, then drop the results into a spreadsheet (you could drop the sql column as the create gets truncated unless you try to fiddle with the delimiters).
Open the exported file (I used NotePad++) in your Editor.
Open a new DB in DB Browser (will refer to it as DBB from now) for SQLite.
In DBB in EXEC SQL tab, input PRAGMA integrity_check, run to check.
Create new tab (for next SQL).
Switch to Spreadsheet and copy the first table name that isn't marked as done.
Switch to Editor do find on EXISTS copied_table_name
Select the section (i.e the CREATE statement along to and including the last row to be inserted, note can be a pain for the larger tables so might be easier to create separate export for those tables). Copy the selection to the clipboard.
Paste into the empty tab and run.
If OK then
in DBB click to create a new tab for the next
switch to spreadsheet and mark table as DONE
goto 5.
If not OK then
If you can fix the issue by altering the SQL fix the SQL (e.g. column name needs enclosing/wrapping/quoting) and then go to 9.
If the issue is due to Constraints then go to 5 but select the table causing the constraint.
OK the issue with the DiscordUser/Club tables is that a Clubs.Ownerid requires a DiscordUser. So clubs cannot be added without the relevant Discord users (id's 1,2,7,14 and 32). Some DiscordUsers are club members so they require a club to exist.
What I have done is to load the DiscordUsers rows for the Club owners changing their ClubId to null. Load the Clubs. Update the ClubId's of the DiscordUsers so they are members of the club that they were before (i.e. undo the null) and to load the rest of the nearly 600 Discordusers (excluding those already loaded).
Here's the SQL I used for that part (note except for the Discorduser, Clubs and the 3 waifu tables, all other tables have been successfully created and loaded).
INSERT INTO `DiscordUser` (Id,AvatarId,Discriminator,UserId,DateAdded,Username,ClubId,LastLevelUp,NotifyOnLevelUp,LastXpGain,TotalXp,IsClubAdmin,CurrencyAmount) VALUES
-- ClubId was 6 changed to null
(1,'6d5212a0f5e862d57c8ffc6f254a2e85','1458',299779864045682689,'2017-10-07 18:02:04.8287878','Anubis',NULL,'2018-03-27 02:22:26.362966',0,'2017-11-17 01:19:14.0313957',7056,1,280),
-- Owns a club but not in a club
(2,'3b37e0f635706f81fdde2b6de9889283','9810',181200115539640321,'2017-10-07 18:04:39.767728','AnnaHime',NULL,'2018-01-02 02:27:38.8011863',0,'2017-11-16 01:29:49.0371488',429,0,360),
-- ClubId null was 3
(7,'612c67b6eb57d8806dcc92ed45b3a6d0','0396',177502331582021639,'2017-10-07 18:11:09.7830603','Tsuchimursu',NULL,'2018-03-28 17:45:53.7399883',0,'2017-11-17 15:53:59.084885',18156,1,4725),
-- ClubId null was 4
(14,'b2dd362171277337294de325bf92ad6a','3267',215597863441268737,'2017-10-07 18:45:54.8092675','LaLa☆Star',NULL,'2018-01-14 20:52:15.7531274',0,'2017-11-08 19:00:22.7778305',2061,1,286),
-- ClubId null was 5
(32,'667f4d802b977c4d4be974e35ae63c55','2593',251689019929395200,'2017-10-08 00:58:16.6089546','username',NULL,'2018-03-28 07:27:34.9348084',0,'2017-11-17 20:02:14.0283998',4704,1,1188),
-- ClubId was 2 changed to NULL
(91,'0adb399c9f2cd94370038e2452ab8c8d','6790',346513954966863872,'2017-10-13 05:48:51.7788964','mayoi',NULL,'2018-03-24 02:50:06.8970518',0,'2017-11-17 20:01:29.0692552',7635,1,515)
;
INSERT INTO `Clubs` (Id,DateAdded,Discrim,ImageUrl,MinimumLevelReq,Name,OwnerId,Xp,Description) VALUES
(2,'2017-11-14 07:39:57.5091592',1,'https://lh3.googleusercontent.com/_7WKFouxTx1fdFpnmmuykDAd5SoiiJOPzHdRmXKOmRRZhV5Ba4V_kZct5ooVjQ9BuzU=w300',5,'We ⤠waifus',91,40137,'Love your waifus short & tall, big & small, cute as dolls, we love ''em all!'),
(3,'2017-12-11 07:00:59.3762914',1,'',30,'Den of Faes',7,11607,NULL),
(4,'2017-12-11 07:03:59.093402',1,'',5,'Skeleton Enthusiasts',14,657,NULL),
(5,'2017-12-11 07:05:56.9111719',1,'',5,'Saki''s Juice',32,2610,NULL),
(6,'2017-12-22 04:46:24.7271709',1,'',5,'nap pile',1,24870,'For the sleeping beauties and the wandering insomniacs who enjoy a good night sleep.')
;
UPDATE `DiscordUser` SET ClubId = 6 WHERE Id=1;
UPDATE `DiscordUser` SET ClubId = 3 WHERE Id=7;
UPDATE `DiscordUser` SET ClubId = 4 WHERE Id=14;
UPDATE `DiscordUser` SET ClubId = 5 WHERE Id=32;
UPDATE `DiscordUser` SET ClubId = 2 WHERE Id=91;
-- LOAD Remaining DiscordUser rows (note incomplete)
INSERT INTO `DiscordUser` (Id,AvatarId,Discriminator,UserId,DateAdded,Username,ClubId,LastLevelUp,NotifyOnLevelUp,LastXpGain,TotalXp,IsClubAdmin,CurrencyAmount) VALUES
--(1,'6d5212a0f5e862d57c8ffc6f254a2e85','1458',299779864045682689,'2017-10-07 18:02:04.8287878','Anubis',6,'2018-03-27 02:22:26.362966',0,'2017-11-17 01:19:14.0313957',7056,1,280),
--(2,'3b37e0f635706f81fdde2b6de9889283','9810',181200115539640321,'2017-10-07 18:04:39.767728','AnnaHime',NULL,'2018-01-02 02:27:38.8011863',0,'2017-11-16 01:29:49.0371488',429,0,360),
(3,'a3cd92d397ad357834d0e6c9f10bfc59','0429',145356302347010048,'2017-10-07 18:04:49.786657','Rebel Lucy',NULL,'2018-03-26 12:55:21.1149964',0,'2017-11-17 22:21:24.0263741',6876,0,3600),
(4,'7225dccaab1c93896657a61e18595378','5286',84689434536050688,'2017-10-07 18:05:44.765554','scarletflame234',NULL,'2018-03-28 22:56:28.7427437',0,'2017-11-17 23:21:41.4446535',13368,0,288),
(5,'c1316bc0673f4a2709b3ce550ed54395','0760',303279191116480514,'2017-10-07 18:06:39.7664015','zachary',NULL,'2018-03-02 03:48:43.4817755',0,'2017-11-17 18:44:14.1082867',210,0,50),
(6,'2ed95eae7c3088c46b23e71578dacc42','8801',161369834314137601,'2017-10-07 18:07:04.7672808','Kou',NULL,'2018-03-07 06:24:32.3405246',0,'2017-11-17 23:20:00.0648699',2640,0,55),
--(7,'612c67b6eb57d8806dcc92ed45b3a6d0','0396',177502331582021639,'2017-10-07 18:11:09.7830603','Tsuchimursu',3,'2018-03-28 17:45:53.7399883',0,'2017-11-17 15:53:59.084885',18156,1,4725),
(8,'5b1d239935ab4dd6d3eee98954601d52','9859',179093512610906113,'2017-10-07 18:13:54.7939334','TheCorty',NULL,'2017-11-12 12:07:36.4752178',0,'2017-11-12 23:47:26.4744132',2460,0,205), ...........
NOTE The SQL from -- LOAD Remaining DiscordUser rows, will not work as it's only intended to show how ID's 1,2 and 7 have been commented out, as should be rows 14, 32 and 91 as they have already been loaded, the other close to 600 rows should be included.
Note I've just also loaded the outstanding 3 waifu tables so all data can be retrieved (assuming that none has been lost due to the corruption). PRAGMA integrity_check; returns OK.

Adding Row in existing table (SQL Server 2005)

I want to add another row in my existing table and I'm a bit hesitant if I'm doing the right thing because it might skew the database. I have my script below and would like to hear your thoughts about it.
I want to add another row for 'Jane' in the table, which will be 'SKATING" in the ACT column.
Table: [Emp_table].[ACT].[LIST_EMP]
My script is:
INSERT INTO [Emp_table].[ACT].[LIST_EMP]
([ENTITY],[TYPE],[EMP_COD],[DATE],[LINE_NO],[ACT],[NAME])
VALUES
('REG','EMP','45233','2016-06-20 00:00:00:00','2','SKATING','JANE')
Will this do the trick?

Your statement looks ok. If the database has a problem with it (for example, due to a foreign key constraint violation), it will reject the statement.
If any of the fields in your table are numeric (and not varchar or char), just remove the quotes around the corresponding field. For example, if emp_cod and line_no are int, insert the following values instead:
('REG','EMP',45233,'2016-06-20 00:00:00:00',2,'SKATING','JANE')

Inserting records into a database has always been the most common reason why I've lost a lot of my hairs on my head!
SQL is great when it comes to SELECT or even UPDATEs but when it comes to INSERTs it's like someone from another planet came into the SQL standards commitee and managed to get their way of doing it implemented into the final SQL standard!
If your table does not have an automatic primary key that automatically gets generated on every insert, then you have to code it yourself to manage avoiding duplicates.
Start by writing a normal SELECT to see if the record(s) you're going to add don't already exist. But as Robert implied, your table may not have a primary key because it looks like a LOG table to me. So insert away!
If it does require to have a unique record everytime, then I strongly suggest you create a primary key for the table, either an auto generated one or a combination of your existing columns.
Assuming the first five combined columns make a unique key, this select will determine if your data you're inserting does not already exist...
SELECT COUNT(*) AS FoundRec FROM [Emp_table].[ACT].[LIST_EMP]
WHERE [ENTITY] = wsEntity AND [TYPE] = wsType AND [EMP_COD] = wsEmpCod AND [DATE] = wsDate AND [LINE_NO] = wsLineno
The wsXXX declarations, you will have to replace them with direct values or have them DECLAREd earlier in your script.
If you ran this alone and recieved a value of 1 or more, then the data exists already in your table, at least those 5 first columns. A true duplicate test will require you to test EVERY column in your table, but it should give you an idea.
In the INSERT, to do it all as one statement, you can do this ...
INSERT INTO [Emp_table].[ACT].[LIST_EMP]
([ENTITY],[TYPE],[EMP_COD],[DATE],[LINE_NO],[ACT],[NAME])
VALUES
('REG','EMP','45233','2016-06-20 00:00:00:00','2','SKATING','JANE')
WHERE (SELECT COUNT(*) AS FoundRec FROM [Emp_table].[ACT].[LIST_EMP]
WHERE [ENTITY] = wsEntity AND [TYPE] = wsType AND
[EMP_COD] = wsEmpCod AND [DATE] = wsDate AND
[LINE_NO] = wsLineno) = 0
Just replace the wsXXX variables with the values you want to insert.
I hope that made sense.

SQL Server identity column inserted 0 value with seed of 1

This is somewhat related to question: SQL server identity column values start at 0 instead of 1
But I'm not sure what happening here. We have our "blank" database which we use to start customer's accounts. We do that by backing up and restoring database.
Customer gets completely blank tables after restore. Example of table, all our tables have PKs exactly like this one:
CREATE TABLE [dbo].[RNPRatePlanStop]
(
[RatePlanStopKey] [int] IDENTITY(1,1) NOT NULL,
[RatePlanKey] [int] NOT NULL,
.....
)
Once in a while (not always and not on all tables) when new record inserted - 0 not expected 1 inserted. I'm not sure how this can be fixed or what I'm doing wrong. This is causing problems in UI because we don't count on having 0 keys..

Also declaration is IDENTITY(1,1) when I run command like this:
SELECT IDENT_CURRENT('RNPRatePlanStop')
It returned 0. For this table and about 7 other tables. Don't know how that was possible, maybe because IDENTITY was applied later via script.
Solution was to "seed" proper identity on those tables:
DBCC CHECKIDENT(RNPRatePlanStop, RESEED, 1)
After that - they all reset correctly and all is well. Still a mistery how those few out of a 100+ tables ended up like so.

Editing an oracle table after copying it

I have an oracle table with 2 columns, both of them are using NUMBERS data type, When I enter any number starting with 0 it removes the 0. So the solution is to change the data type to VARCHAR2. I have a script that
creates a temp table with VARCHAR2 and primary key
copies the old table
Drops the old table
Renames the temp to the old table
However I'm facing an issue. When copying the table, any data that was truncated before remains that way, is there anyway I can add a 0 at the start of the old data?. Below is the script I have created.
/* create a new table named temp */
CREATE TABLE TEMP_TABLE
(
IMEISV_PREFIX VARCHAR2(8),
IMEI_FLAG NUMBER(2),
CONSTRAINT IMEIV_PK PRIMARY KEY (IMEISV_PREFIX)
);
/* copy everything from the old table to the new temp table */
INSERT INTO TEMP_TABLE
SELECT * FROM REF_IMEISV_PREFIX;
/* Delete the original table */
DROP TABLE REF_IMEISV_PREFIX;
/* Rename the temp table to the original table */
RENAME TEMP_TABLE TO REF_IMEISV_PREFIX;

No there is not. When Oracle saves the data to the database, it saves it in the format at that time. All other information is removed. There is no way to restore historic data.
In fact, when you stored the data to the database before, let's say you do this:
insert into tableX (anumber) values ('01');
In fact it does:
insert into tableX (anumber) values (to_number('01'));
So it is lost from the very beginning. (Note that the example is actually a bad habit! You should never rely on casting in the database, always hand over the data in the right data type!)

If you need to show that leading zero your problem is a interface problem, not a database problem. You can format your output to show how many leading zero do you want.
If the data is a number let it as is.