SQL LOADER Control File without fields - oracle

I'm working on a task to load Database table from a flat file. My database table has 60 columns.
Now, In SQL LOADER control file, Is it mandatory to mention all the 60 fields ?
Is there a way to tell SQL LOADER that all 60 columns should be treated as required without mentioning the fields in the Control File ?

Oracle 12c (and higher versions) offer express mode.
In a few words (quoting the document):
The SQLLoader TABLE parameter triggers express mode. The value of the TABLE parameter is the name of the table that SQLLoader will load. If TABLE is the only parameter specified, then SQL* loader will do the following:
Looks for a data file in the current directory with the same name as the table being loaded that has an extension of ".dat". The upper/lower case used in the name of the data file is the same as the case for the table name specified in the TABLE parameter
Assumes the order of the fields in the data file matches the order of the columns in the table
Assumes the fields are terminated by commas, but there is no enclosure character
(...) order of the fields in the data file matches the order of the columns in the table. The following SQL*Loader command will load the table from the data file.
sqlldr userid=scott table=emp
Notice that no control file is used. After executing the SQL*Loader command, a SELECT from the table will return (...)
I guess that's what you're after.

Related

Creating txt file using Pentaho

I'm currently trying to create txt files from all tables in the dbo schema
I have like 200s-300s tables there, so it would takes up too much times to create it manually..
I was thinking for creating a loop.
so as example (using AdventureWorks2019) :
select t.name as table_name
from sys.tables t
where schema_name(t.schema_id) = 'Person'
order by table_name;
This would get all the table name within the Person schema.
So I would loop :
Table input : select * from ${table_name}
But then i realized that for txt files, i need to declare all the field and their data types in pentaho, so it would become a problems.
Any ideas how to do this "backup" txt files?
Using Metadata Injection and more queries to the schema catalog tables in SQL Server. You not only need to retrieve the table name, you would need to afterwards retrieve the columns in that table and the data types, and inject that information (metadata) to the text output step.
You have in the samples directory of your spoon installation an example on how to use Metadata Injection, use it, along with the documentation, to build a simple example (the check to generate a transformation with the metadata you have injected is of great use to debug)
I have something similar to copy data from one database to another, both in Oracle, but with SQL Server you have similar catalog tables as in Oracle to retrieve the information you need. I created a simple, almost empty transformation to read one table and write to another. This transformation has almost no information, only the database origin in the Table Input step and the target database in the Table Output step:
And then I have a second transformation where I fill up all the information (metadata) to inject: The query to perform in the Table Input step, and all the data I need in the Table Output: Target table, if I need to truncate before inserting, the columns from (stream field) and to (Table field):

How to handle new line characters in hive?

I am exporting table from Teradata to Hive.. The table in the teradata Has a address field which has New line characters(\n).. initially I am exporting the table to mount filesystem path from Teradata and then I am loading the table into hive... Record counts are mismatching between teradata table and hive table, Since new line characters are presented in hive.
NOTE: I don't want to handle this through sqoop to bring the data I want to handle the new line characters while loading Into hive from local path.
I got this to work by creating an external table with the following options:
ROW FORMAT DELIMITED FIELDS TERMINATED BY '\001'
ESCAPED BY '\\'
STORED AS TEXTFILE;
Then I created a partition to the directory that contains the data files. (my table uses partitions)
i.e.
ALTER TABLE STG_HOLD_CR_LINE_FEED ADD PARTITION (part_key='part_week53') LOCATION '/ifs/test/schema.table/staging/';
NOTE: Be sure that when creating your data file you use '\' as the escape character.
Load data command in Hive only copies the data directly into the hdfs table location.
The only reason Hive would split a new line is if you only defined the table stored as TEXT, which by default uses new lines as record separators, not field separators.
To redefine the table you need something like
ROW FORMAT DELIMITED
FIELDS TERMINATED BY ',' ESCAPED BY 'x'
LINES TERMINATED BY 'y'
Where, x and y are, hopefully, escape characters around fields containing new lines, and record delimiters, respectively

SQL Loader in Oracle

As I am inserting data from a CSV file to a oracle table using SQL Loader and it is working fine .
LOAD DATA
INFILE DataOut.txt
BADFILE dataFile.bad
APPEND INTO TABLE ASP_Net_C_SHARP_Articles
FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"'
(ID,Name,Category)
above settings are being used to do that but I do not want to specify any of the column name ex. (ID,Name,Category) .
Is this possible or not if yes can anybody tell me how..
In SQL*Loader you need to specify the column names. If you still persist in ignoring the column names in the control file, then I would suggest you to use SQL to "discover" the name of the columns and dynamically generate the control file and wrap it via shell script to make it more automated.
Meanwhile, you can consider External Tables which uses the SQL*Loader engine, so you will still have to perform some dynamic creation here for your input file as suggested above. But you can create a script to scan the input file and dynamically generate the CREATE TABLE..ORGANIZATION EXTERNAL command for you. Then the data becomes available as if it were a table in your database.
You can also partially skip the columns if that would help you, by using FILLER. BOUNDFILLER (available with Oracle 9i and above) can be used if the skipped column's value will be required later again.

Have dynamic columns in external tables

My requirement is that I have to use a single external table in a store procedure for different text files which have different columns.
Can I use dynamic columns in external tables in Oracle 11g? Like this:
create table ext_table as select * from TBL_test
organization external (
type oracle_loader
default directory DATALOAD
access parameters(
records delimited by newline
fields terminated by '#'
missing field values are null
)
location ('APD.txt')
)
reject limit unlimited;
The set of columns that are defined for an external table, just like the set of columns that are defined for a regular table, must be known at the time the external table is defined. You can't choose at runtime to determine that the table has 30 columns today and 35 columns tomorrow. You could also potentially define the external table to have the maximum number of columns that any of the flat files will have, name the columns generically (i.e. col1 through col50) and then move the complexity of figuring out that column N of the external table is really a particular field to the ETL code. It's not obvious, though, why that would be more useful than creating the external table definition properly.
Why is there a requirement that you use a single external table definition to load many differently formatted files? That does not seem reasonable.
Can you drop and re-create the external table definition at runtime? Or does that violate the requirement for a single external table definition?

Loading multiple concatenated CSV files into Qracle with SQLLDR

I have a dump of several Postgresql Tables in a selfcontained CSV file which I want to import into an Oracle Database with a matching schema. I found several posts on how to distribute data from one CSV "table" to multiple Oracle tables, but my problem is several DIFFERENT CVS "tables" in the same file.
Is it possible to specify table separators or somehow mark new tables in an SQLLDR control file, or do I have to split up the file manually before feeding it to SQLLDR?
That depends on your data. How do you determine which table a row is destined for? If you can determine which table base on data in the row, then it is fairly easy to do with a WHEN.
LOAD DATA
INFILE bunchotables.dat
INTO TABLE foo WHEN somecol = 'pick me, pick me' (
...column defs...
)
INTO TABLE bar WHEN somecol = 'leave me alone' (
... column defs
)
If you've got some sort of header row that determines the target table then you are going to have to split it before hand with another utility.

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