What is control file?
It describe how to interpret the flat file and options to load the data.
It describe the location and format of the data file.
It describe the location of the Bad and Discard records file .
It has the control to connect database
What are the mandatory options in the control(*.ctl) file.
LOAD DATA, INFILE, COLUMNS OF THE TARGET TABLE
BADFILE
DISCARDFILE
LOADING OPTIONS, FILE FORMATTER
Pick the correct options about Control File
The LOAD DATA statement is required at the beginning of the control file.
The INFILE option specifies where the input file is located
Specifying BADFILE, then bad records found during loading will be stored in this file.
Specifying DISCARDFILE , then records which do not meet a WHEN condition will be written to this file.
Field Seperator - how the fields are separated in input file.
what are the loading options allowed in sqlldr
INSERT
APPEND
REPLACE TRUNCATE
DELETE UPDATE
Pick the correct options about loading parameters
INSERT : Loads rows only if the target table is empty
APPEND: Load rows if the target table is empty or not.
REPLACE: First deletes all the rows in the existing table and then, load rows.
TRUNCATE: First truncates the table and then load rows.
What are the two types of loads used by oracle sqldr
Conventional
Direct
Indirect
Insert
Conventional type is the default load type used by Sql Loader
True
False
Conventional path load (the default) uses the SQL INSERT statement and a bind array buffer to load data into database tables. When SQL*Loader performs a conventional path load, it wont competes equally with all other processes for buffer resources. This can slow the load significantly. Extra overhead is added as SQL statements are generated, passed to Oracle, and executed. Although appropriate during normal use, this can slow bulk loads dramatically.
In Direct Path Loading, Oracle will not use SQL INSERT statement for loading rows. It directly writes the rows, into fresh blocks beyond High Water Mark, in datafiles i.e. it does not scan for free blocks before high water mark. Direct Path load is very fast because Partial blocks are not used, so no reads are needed to find them, and fewer writes are performed. SQL*Loader need not execute any SQL INSERT statements; therefore, the processing load on the Oracle database is reduced. A direct path load calls on Oracle to lock tables and indexes at the start of the load and releases them when the load is finished. During a direct path load, processes perform their own write I/O, instead of using Oracle's buffer cache. This minimizes contention with other Oracle users.