Rule Definition
CHAR should be used for storing fix length character strings. String values will be space padded before stored on disk. If this type is used to store variable length strings, it will waste a lot of disk space.
So, Oracle suggests to use VARCHAR2 instead of CHAR while declaring datatype.
Also VARCHAR is going to be replaced by VARCHAR2 in future so Oracle recommends to replace VARCHAR by VARCHAR2.
Remediation
Change CHAR columns to VARCHAR2.
Change VARCHAR columns to VARCHAR2.
Related Technologies
PL/SQL
Technical Criterion
Efficiency - Memory, Network and Disk Space Management
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