Oracle 12c – Logically There Is A Redo Group But Not Physically – Database Can’t Open

I have an Oracle 12c Database for my enterprise manager.

I could not connect to enterprise manager because the database was closed.

I opened listener. However, the database remained mounted mode. When I want to open the database in read & write mode, I get the error as follows:

SQL> alter database open;

ERROR at line 1:

ORA-00313: open failed for members of log group 3 of
thread 1

ORA-00312: online log 3 thread 1:

ORA-27037: unable to
obtain file status

Linux-x86_64 Error: 2: No such file or directory
Additional information: 3

When I go to the file location of redo03, there is no redo03.

So it’s logically, but not physically.

There are some queries and results:

SQL> col member format a50
SQL> select group#, type, member from v$logfile;

---------- ------- --------------------------------------------------
         3 ONLINE  /path/of/redo/redo03.log
         2 ONLINE  /path/of/redo/redo02.log
         1 ONLINE  /path/of/redo/redo01.log
         4 ONLINE  /path/of/redo/redo04.log

SQL> select group#, thread#, sequence#, bytes/1024/1024, members, status from v$log;

---------- ---------- ---------- --------------- ---------- ----------------
         1          1      61525              50          1 INACTIVE
         4          1          0              50          1 UNUSED
         3          1      61527              50          1 CURRENT
         2          1      61526              50          1 INACTIVE

I tried doing this: create redo group 4. Drop redo group 3 and recreate redo group 3.

There was no problem creating redo group 4. I used this command below:

alter database add logfile thread 1 group 4 '/path/of/redo/redo04.log' size 50m;

But when I want to drop group 3, it gives error as follows:


ERROR at line 1:

ORA-01623: log 3 is current log for instance dbname (thread 1) –
cannot drop

ORA-00312: online log 3 thread 1: ‘/path/of/redo/redo03.log’

I wanted to try disable the thread that redo group is connected to and after that I wanted to drop redo group 3. But it give error as follows:

SQL> select thread#, status, enabled from v$thread;

---------- ------ --------
         1 OPEN   PUBLIC

SQL> alter database disable thread 1;
alter database disable thread 1

ERROR at line 1:

ORA-01109: database not open

When I try to switch logfile, it gives error as follow:

SQL> alter system switch logfile;
alter system switch logfile

ERROR at line 1:

ORA-01109: database not open

As a result; there is a redo group 3 logically but there is no physically file. I am sure that nobody has deleted the file because I checked it with the history command on linux system. I can’t open the database because redo group 3 cannot find. I can’t logfile switch, I can’t disable thead, I can’t delete redo group 3 and recreate it. Please can you help with this?

Best regards,

Existe realmente um melhor database? MySQL ou PostgreSQL? ou é simplesmente gosto?

Estou estudando faz 1 ano programação, já me dou com front-end e uso PHP + db no back
Pra melhorar meus futuros sites, é melhor eu usar o PostgreSQL ou MySQL?

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I am using Javascript on Applab. I have the code:

var player = {};
player.Username=" ";
onEvent("confirmUsernameButton", "click", function() {
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However, it is not updating the database at all. Can I update the database with an without referring to the id number, or could I use each user’s specific “User ID” to update the database instead? Any help is appreciated.’

Link to app:
To access the code and database, press “view code” at the top right corner of the screen.

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enter image description here

As you can see by looking at my checksum colum on the left, there are 8 different schemas from 1995 through 2019. Also, you can see that the data between each can vary quite a bit. I’ve color-coded columns that are logically similar. Sometimes the data is mostly the same but the names of the columns have changed. Sometimes, there is different data altogether that appears or disappears.

I think it is pretty clear that the best goal here is to have 1 table combining all of this information rather than 8 disparate tables, since I want to be able to query across all of them efficiently. Each table contains ~150,000 rows so the table would have around 4 million records. Each table has 55-60 fields approximately.

I’ve been struggling for a few days with how to tackle it. Half of the files were fixed-width text files, not even CSVs, so it took me a long time to properly convert those. The rest are thankfully already CSVs or XLSX. From here, I would like to end up with a table that:

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  • has no loss of data

Additionally, there are other caveats such as:

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  • data is heavily denormalized but does not need to be normalized
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I basically just want to stack the tables top to bottom into one big table, more or less.

I’ve considered a few approaches:

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I’ve tried importing just the first table into both SQL Server and Access but have encountered issues there with their inability to parse the data (e.g. duplicate columns, flagging columns with textual data as integers). In any case, it’s not practical to manually deal with schema issues for each file. My next inclination was to kind of patchwork this together in Excel, which seems the most intuitive, but Excel can’t handle a spreadsheet that large so that’s a no-go as well.

The ultimate goal is to have one large (probably multi-GB) SQL file that I can copy to the database server and run, maybe using LOAD IN FILE or something of that sort – but with the data all ready to go since it would be unwieldy to modify afterwards.

Which approach would be best? Additionally, what tools should I be using for this? Basically the problem is trying to “standardize” this data with a uniform schema without losing any data and being as non-redundant as possible. On the one hand, it doesn’t seem practical to go through all 25 tables manually and try to get them imported or try to change the schema on each one. I’m also not sure about trying to figure out the schema now and then modifying the data, since I can’t work with it all at once? Any advice from people who have done stuff like this before? Much appreciated!

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enter image description here

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enter image description here

So this design above is correct and I have no problem with it.

However, I also thinking of a more simple design like this

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1  Jake 1
2  Jake 2
3  John 1

id name
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Because this WordPress lives on a shared hosting environment, my options (for daily automated backups not managed by most host) are a little limited.

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I decided to test the MySQL database for restorability today by trying to import it, via phpmyadmin, into another Cpanel.

These are the settings that I used.

enter image description here

The import fails with the following message:

enter image description here

It’s been years since I did much with MySQL databases. Could anybody point me in the right direction to try figure out what exactly is failing? It would be much appreciated.

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