Oracle Common data type description _oracle

Type	Meaning	Storage description	Note
CHAR	Fixed-length strings	Max length 2000bytes
VARCHAR2	Variable-length strings ,	Max length 4000bytes	Maximum length of the index can be 749
NCHAR	Fixed-length string based on character set	Max length 2000bytes
NVARCHAR2	Variable-length strings based on character set	Max length 4000bytes
DATE	Date (Day - month - year)	Dd-mm-yy (HH-MI-SS), after rigorous testing, no thousand bug problem
TIMESTAMP	Date (Day - month - year)	Dd-mm-yy (HH-MI-SS:FF3), after rigorous testing, no thousand bug problem	compared to DATE,TIMESTAMP has a decimal bit of information
LONG	Super Long string	Max length 2G, enough to store voluminous books
RAW	Fixed-length binary data	Max length 2000bytes	can store multimedia image sound, etc.
LONG RAW	Variable-length binary data	Max length 2G	can store multimedia image sound, etc.
Blob	Binary data	Max length 4G
Clob	Character data	Max length 4G
NCLOB	Character data based on character set	Max length 4G
BFILE	Binary data stored outside the database	Max length 4G
ROWID	Unique row numbers for records in a datasheet	10bytes	. ****.**** format,* 0 or 1
Nrowid	Unique row numbers for records in a binary datasheet	Max length 4000bytes
Number (P,s)	Number Type	P is integer digit,S is decimal digit
DECIMAL (P,s)	Number Type	P is integer digit,S is decimal digit
INTEGER	Integer type	A small integer
FLOAT	Floating-point number type	Number (number), double precision
Real	Real type	Number (a), higher accuracy