Different types of database

- - How many types of data, a total of 
the SELECT  DISTINCT data_type from user_tab_cols;

LONG
NVARCHAR2
TIMESTAMP(6)
FLOAT
NUMBER
CHAR
CLOB
UROWID
NCHAR
DATE
RAW
VARCHAR2
BLOB

- - kind of system which involves the type of table, of course, some data types are not incorporated. We'll add it. 
SELECT t.TABLE_NAME, t.COLUMN_NAME, t.DATA_TYPE, t.DATA_LENGTH, t.DATA_PRECISION, t.DATA_SCALE, t.LOW_VALUE, t.HIGH_VALUE from user_tab_cols T   WHERE   t.DATA_TYPE = ' a LONG ' ;
 SELECT t.TABLE_NAME, T .COLUMN_NAME, t.DATA_TYPE, t.DATA_LENGTH, t.DATA_PRECISION, t.DATA_SCALE, t.LOW_VALUE, t.HIGH_VALUE from user_tab_cols T   WHERE   t.DATA_TYPE = ' NUMBER ' ;
 SELECT t.TABLE_NAME, t.COLUMN_NAME, t.DATA_TYPE , t.DATA_LENGTH, t.DATA_PRECISION, t.DATA_SCALE, t.LOW_VALUE, t.HIGH_VALUE from user_tab_cols t  where  t.DATA_TYPE='FLOAT';

select t.TABLE_NAME,t.COLUMN_NAME,t.DATA_TYPE,t.DATA_LENGTH,t.DATA_PRECISION,t.DATA_SCALE,t.LOW_VALUE,t.HIGH_VALUE from user_tab_cols t  where  t.DATA_TYPE='DATE';
select t.TABLE_NAME,t.COLUMN_NAME,t.DATA_TYPE,t.DATA_LENGTH,t.DATA_PRECISION,t.DATA_SCALE,t.LOW_VALUE,t.HIGH_VALUE from user_tab_cols t  where  t.DATA_TYPE='TIMESTAMP(6)';

select t.TABLE_NAME,t.COLUMN_NAME,t.DATA_TYPE,t.DATA_LENGTH,t.DATA_PRECISION,t.DATA_SCALE,t.LOW_VALUE,t.HIGH_VALUE from user_tab_cols t  where  t.DATA_TYPE='CHAR';
select t.TABLE_NAME,t.COLUMN_NAME,t.DATA_TYPE,t.DATA_LENGTH,t.DATA_PRECISION,t.DATA_SCALE,t.LOW_VALUE,t.HIGH_VALUE from user_tab_cols t  where  t.DATA_TYPE='NCHAR';
select t.TABLE_NAME,t.COLUMN_NAME,t.DATA_TYPE,t.DATA_LENGTH,t.DATA_PRECISION,t.DATA_SCALE,t.LOW_VALUE,t.HIGH_VALUE from user_tab_cols t  where  t.DATA_TYPE='VARCHAR2';
select t.TABLE_NAME,t.COLUMN_NAME,t.DATA_TYPE,t.DATA_LENGTH,t.DATA_PRECISION,t.DATA_SCALE,t.LOW_VALUE,t.HIGH_VALUE from user_tab_cols t  where  t.DATA_TYPE='NVARCHAR2';
select t.TABLE_NAME,t.COLUMN_NAME,t.DATA_TYPE,t.DATA_LENGTH,t.DATA_PRECISION,t.DATA_SCALE,t.LOW_VALUE,t.HIGH_VALUE from user_tab_cols t  where  t.DATA_TYPE='CLOB';

select t.TABLE_NAME,t.COLUMN_NAME,t.DATA_TYPE,t.DATA_LENGTH,t.DATA_PRECISION,t.DATA_SCALE,t.LOW_VALUE,t.HIGH_VALUE from user_tab_cols t  where  t.DATA_TYPE='UROWID';

select t.TABLE_NAME,t.COLUMN_NAME,t.DATA_TYPE,t.DATA_LENGTH,t.DATA_PRECISION,t.DATA_SCALE,t.LOW_VALUE,t.HIGH_VALUE from user_tab_cols t  where  t.DATA_TYPE='RAW';
select t.TABLE_NAME,t.COLUMN_NAME,t.DATA_TYPE,t.DATA_LENGTH,t.DATA_PRECISION,t.DATA_SCALE,t.LOW_VALUE,t.HIGH_VALUE from user_tab_cols t  where  t.DATA_TYPE='BLOB';