Handle Null Values In Sql: Loader
: Useful if your source system uses a placeholder like "N/A" or "0". column_name NULLIF (column_name = "N/A") Use code with caution. Copied to clipboard
: Useful for fixed-width files or fields that might contain spaces. column_name NULLIF (column_name = BLANKS) Use code with caution. Copied to clipboard 3. Using the DEFAULTIF Clause Handle Null Values In Sql Loader
The NULLIF clause is the most common way to explicitly define when a field should be treated as null. It tests a condition; if true, it sets the column to NULL. : Useful if your source system uses a
You can also use Oracle SQL functions within the control file to handle null logic during the load process. This is helpful for replacing nulls with a specific value (like NVL ). column_name "NVL(:column_name, 'Unknown')" Use code with caution. Copied to clipboard Summary of Key Commands NULLIF Sets column to NULL if a specific condition is met. DEFAULTIF Uses the database's default value if a condition is met. TRAILING NULLCOLS Prevents errors when the last columns in a row are missing. BLANKS column_name NULLIF (column_name = BLANKS) Use code with
Handling null values in SQL*Loader involves managing how data from your flat file is interpreted and loaded into Oracle database tables. You can control this behavior using specific clauses in your control file ( .ctl ). 1. Default Behavior
If your data file has records where the last few columns are often empty, SQL Loader might throw an error because it expects more delimiters. Use the TRAILING NULLCOLS clause at the table level to tell SQL Loader to treat any missing relative fields at the end of a record as nulls.
A keyword used with NULLIF to identify fields containing only whitespace.
