How to Import many files to an Oracle table - oracle

I want to make a scheduled flow to reading a directory includes CSV files and import them to a Oracle table (I don't know the file names), I've tried ODI (using variables) but ODI needs to know the file_name and if I create a table for the file_names for using with ODI variables, as the daily total files is over 200,000, it may caused problems whether files comes with delay or missed one.
It's appreciated if you could lead me into this matter.

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Oracle user DB export command's scope (User/Schema level)?

I'm totally novice in terms of Oracle DB knowledge. Trying to understand IMPDB command and its scope.
Issue: Suppose there are 500 tables in a particular DB, many of them (60% - 70% or more) are coming as zero records when we're importing the data into a fresh Oracle DB (getting the data from one vendor who has the DB). The doubt is, how can most of the tables be zero records in a DB (why were they created at the first place then?). Also, we're assuming maybe the vendor is using a specific user while generating the .DMP files who has no access to those tables and hence the 0 count. When we asked the vendor, they said, that's not how Oracle works, they've provided user export dump and said, "Schema is a collection of database objects owned by a specific user. Those objects include tables, indexes, views, functions, stored procedures, etc."
When asked about the zero records issue, they said they're pulling correctly and have no understanding as to why so many tables are zero. The SO community has great experts in Oracle DB, can anyone shed some light as to:
What might be the issue?
Is our assumption correct (i.e, that user doesn't have access to those tables which got zero records)?
What's the right way forward?
4) Anything else you want to add.
The vendor is correct - the utility used to generate the export, EXPDP (the compliment to IMPDP) can create a full dump of all of the database objects of a specific user. However, the parameters used to generate the export can vary greatly, and it's absolutely possible for an export to not include table data IF the EXPDP command/parameters used to create the export are specified in that way. For example, let's imagine that someone wants to export a specific schema using the following commmand:
expdp [USER]#[DATABASE] schemas=test directory=DATA_PUMP_DIR dumpfile=test.dmp logfile=test.log query=TEST.TABLE:'"WHERE row_date>sysdate"'
While the export is being generated, all of the rows in that specific table will be evaluated based on the where condition. Unless rows have a date that is in the future, none of the rows dated prior and up to the sysdate will be exported. If a where condition like that is applied to the entire export, you'll have tables with 0 rows in the dump file.
That is just an example - it might also be the case that the tables really have 0 rows. This is possible for a lot of reasons - perhaps it is an older schema with tables that have previously been truncated. Perhaps that particular database isn't used often, and the tables within the schema are empty because rows were never added to the tables. Maybe a developer or another DBA created a bunch of unnecessary tables and they simply were never dropped. It could be a plethora of potential reasons/issues for a schema to have empty tables, and that doesn't mean there is something wrong with the database or the export file being generated. Applications and their technical requirements change all the time, and it's possible that the schema simply wasn't updated when those tables were no longer needed.
The first thing I would recommend is:
Ask the vendor to provide record counts of each table in that schema from their end for validation purposes. This will tell you if the tables are empty in the database. If they are empty in the database, they will be empty in your export. This is very simple and can be achieved with a query like select owner, table_name, num_rows, sample_size, last_analyzed from all_tables where owner=[SCHEMA]; provided that their table statistics are up to date.
If this is a big concern for you, you can always ask them to exclude those tables in the export with a command like:
expdp [USER]#[DATABASE] schemas=test exclude=TABLE:"IN ('Table1', 'Table2')" directory=DATA_PUMP_DIR dumpfile=test.dmp logfile=test.log
Or simply exclude them during your import with a command like:
impdp [USER]#[DATABASE] schemas=test exclude=TABLE:"IN ('Table1', 'Table2')" directory=DATA_PUMP_DIR dumpfile=test.dmp logfile=test.log
Either way should work, but be careful and ensure that there will be no issues from a constraint/child record perspective. You can also exclude the constraints. There are many ways to work around it.
IF THERE ARE INCONSISTENCIES BETWEEN THE COUNTS AND THE ROWS IMPORTED, I would recommend asking the vendor for the specific EXPDP command or parameter file that was used to generate the export. This will let you know if the empty rows are being caused by a clause in the export command.
It's impossible to know if your assumption is correct without knowing more about the database the export is coming from or seeing the the commands being used to generate the export. I would ask the vendor to verify record counts before assuming that it's a permission issue. Empty tables are created all the time.

Oracle Export/Import issues with Tablespace

I created a dump of a local oracle database like this:
expdp mydb/passwd -schemas=myschema -dumpfile=mydumpfile.dmp -logfile=oralog.log
I sent the dump to someone who is supposed to import the dump in his oracle server. Now, he tells me, the import fails due to some errors related to tablespaces (like tablespace XYZ is not available, - the database XYZ is in no relation to the respective database). Besides, he asks me to give some information about the dump concerning the tablespaces.
Since I am usually working with MySQL and have limited knowledge about these Oracle-Tablespace things: I would really appreciate to get some advise.
Use REMAP_TABLESPACE parameter.
For example,
REMAP_TABLESPACE=(source1:destination1,source2:destination1,source3:destination1,source4:destination1)
Go through the documentation about Data Pump Import. A small quote -
Multiple REMAP_TABLESPACE parameters can be specified, but no two can
have the same source tablespace. The target schema must have
sufficient quota in the target tablespace.
Note that use of the REMAP_TABLESPACE parameter is the only way to
remap a tablespace in Data Pump Import. This is a simpler and cleaner
method than the one provided in the original Import utility. That
method was subject to many restrictions (including the number of
tablespace subclauses) which sometimes resulted in the failure of some
DDL commands.
By contrast, the Data Pump Import method of using the REMAP_TABLESPACE
parameter works for all objects, including the user, and it works
regardless of how many tablespace subclauses are in the DDL statement.

Oracle PL/SQL and Shell scripting: from one schema to another schema

I want to load data from one table from one schema to another schema on daily basis.
Tables are in different database so to create database link will not be an option due to some security purpose....
About million records will get process....
Databases are on different server , from database "A" I am fetching Employee presence details by combining emp details and emp presence table for period of a month , and loading this data in other table on database "B". Need to run this activity on daily basis.
I need to run a job daily at low peak hours to get complete copy of table into other db ...
will Import/Export or loading data with help of sqlldr?
please let me know the correct way..
Thanks in Advance..
What are my best options?
Well, it seems that using database link would best fit for your situation. If you want to read a table from a database, you should have read privilege. Perhaps you can ask the DBA creating an account(user) which only has read privilege for specific table. Then you can use database link connecting with the new user.
You can't update or delete data from the table because the user you connecting doesn't have the write privilege. This can solve the security problem.
exp/imp and sqlldr are different tools. They don't work together. You can only import data from an export file. You can't load export file with sqlldr.
If you want to run this periodically, it sounds like you might want to take a look at the Oracle Scheduler
Overview: http://docs.oracle.com/cd/B28359_01/server.111/b28310/schedover001.htm
To export the data and add it into the new database, you might want to use Oracle DataPump, which can do both the export and import for you, securely.
Data Pump Export: http://docs.oracle.com/cd/B28359_01/server.111/b28319/dp_export.htm
So your bet might be creating a shell script that uses data pump to create an export file from database number 2, and then uses data pump again to import said file into database number 1.
Once you have that script, you can schedule it to run during nights or at any time you have low traffic.
Regards

Attempting to use SQL-Developer to analyze a system table dump created with 'exp'

I'm attempting to recover the data from a specific table that exists in a system table dump I performed earlier. I would like to append the rows existing in the dump to any rows that may exist in the active table. The problem is, it's likely that the name of the table in the dump is not the same as what exists in the database currently (They're dynamically created with a prefix of ARC_TREND_). In addition, I don't know the name of the table as it exists in the dump, I was hoping to use SQL Developer to analyze the dump file as I can recognize the correct table by it's columns and it's existing rows.
While i'm going on blind faith that SQL Developer can work with my dump file, when attempting to open it, i'm getting a Java Heap OutOfMemory exception raised. I've adjusted the maximum heap size from 640m to 1024m in both sqldeveloper.bat and in sqldeveloper.conf, but to no avail.
Can someone recommend a course of action for me to take to recover the data from a table which exists in a exp created dump file? A graphical tool would be nice, but I'm no stranger to the command line. I need to analyze the tables that exist in the dump in order to pick the correct one out. Then I assume I can use imp TABLE= to bring it back into the active instance. It likely won't match the existing table name, so I will use SQL Developer to copy the rows from the imported table to the table where I need them to be.
The dump was taken from a Linux server running 10g, and will be imported to (the same server & database instance, upgraded) an 11g instance of the same database.
Thanks
Since you're referring to imp rather than impdp, I assume this wasn't exported with data pump. Either way, I doubt you'll get anything useful through SQL Developer.
Fortunately most of what you're trying to do is quite easy from the command line; just run imp with the INDEXFILE parameter, which will give you a text file containing all the table (commented out with REM) and index creation commands. From that you should be able to spot the table from its column names.
You can't really see any row data though, so if there's more than one possible match you might need to import several tables and inspect the data in them in the database to see which one you really want.

Oracle sql result to DBF file export

I would like to export data from a Oracle table into *.dbf file (like excel) through PL/SQL scripts. Are there any codes available?
There are a number of different ways to do this. The easiest way is to use an IDE like SQL Developer or TOAD, which offer this functionality.
If you want to call it from PL/SQL, then then are no built-in Oracle functions. However, it is relatively straightforward to build something using UTL_FILE which can write out value separated records. These can be picked up in Excel.
Note that the default separator - , (comma being the "C" in .CSV) - will cause problems if your exported data contains commas. So you will need to use the Data Import wizard rather than a right-click Open With ...
Incidentally, it is probably a bad idea to use the .dbf suffix. In an Oracle file system the presumed meaning is database file - i.e. part of the database's infrastructure. This is just a convention, but there is no point in needlessly confusing people. Perferred alternatives include .csv, .dmp or .exp.
edit
If your interest is just to export data for transferring to another Oracle database then you should look at using the Data Pump utility. This comes with an API so it can be used from PL/SQL. Alternatively we unload data through external tables declared with a DataPump driver.
You could also consider using the External Tables feature of Oracle. This essentially allows you to map a CSV file to a 'virtual' table and the you can insert into it (and therefore the file.)
Oracle External Tables Concept Guide

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