What does Trailing Nullcols mean?
The TRAILING NULLCOLS clause tells SQL*Loader to treat any relatively positioned columns that are not present in the record as null columns. See Handling Short Records with Missing Data. The remainder of the control file contains the field list, which provides information about column formats in the table being loaded.
Can I use sequence in SQL Loader?
“The SEQUENCE function generates a unique value in the column LOADSEQ. This function finds the current maximum value in column LOADSEQ and adds the increment (1) to it to obtain the value for LOADSEQ for each row inserted.”
What is Currval and Nextval in SQL?
CURRVAL. returns the current value of a sequence. NEXTVAL. increments the sequence and returns the next value.
How does SQL Loader handle NULL columns?
The SQL*Loader Control File
- the action ( LOAD DATA)
- the file containing the data (INFILE)
- the table to load into.
- The delimiter used in the file (FIELDS TERMINATED BY)
- treat any missing values at the end of a line as null (TRAILING NULLCOLS)
Which are Pseudocolumns examples?
Some of the important Pseudo Columns are as follows:
- NEXTVAL in SQL. With the help of Nextval pseudo column we get the flexibility to increment the sequence.
- CURRVAL in SQL.
- SYSDATE in SQL.
- SQL ROWNUM.
- ROWID in SQL.
- USER in SQL.
What is Oracle Data Pump?
Oracle Data Pump technology enables very high-speed movement of data and metadata from one database to another. Oracle Data Pump is available only on Oracle Database 10g release 1 (10.1) and later.
When to use sqlldr in SQL * loader?
The above indicates that the table should be empty before you can upload data using sql*loader. If you like to insert more data to the tables without having to delete the existing rows, use the “append’ command as shown in the following control file. Now, if you do sqlldr this will append the data.
How to pass userid and password to sqlldr?
You can pass the userid and password to the sqlldr command using any one of the following format. As you see below, both of these will prompt you for control file location, as it was not given in the command line. $ sqlldr scott/tiger (or) $ sqlldr userid=scott/tiger control = SQL*Loader-287: No control file name specified.
What does the log file indicate in sqlldr?
The log file indicates that 2 records are rejected as shown below: Control File: /home/ramesh/sqlldr-bad.ctl Data File: /home/ramesh/employee-bad.txt Bad File: /home/ramesh/employee-bad.bad Discard File: none specified Table EMPLOYEE: 3 Rows successfully loaded. 2 Rows not loaded due to data errors.
How to execute sqlldr on an empty table?
$ sqlldr scott/tiger (or) $ sqlldr userid=scott/tiger control = SQL*Loader-287: No control file name specified. Execute the sqlldr command to upload these new record to the empty table by specifying both uid/pwd and the control file location as shown below.