Oracle queries all tables and sqlplus set column widths under the current user

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[Email protected] ~]$ sqlplus scott/[email Protected]/prod

Sql*plus:release 11.2.0.3.0 Production on Thu Apr 13 19:49:57 2017

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Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0-64bit Production
With the partitioning, OLAP, Data Mining and Real application testing options

Sql> select table_name from tabs;

table_name
------------------------------
DEPT
Emp
BONUS
Salgrade

Sql> Select table_name from User_tables;

table_name
------------------------------
DEPT
Emp
BONUS
Salgrade

Column widths of type number are set in 99999 or 999,99 format.

99999 means the column width is set to five digits, and999,99 indicates that the column width is set to 6 digits because the comma is counted as one.

Sql> select * FROM dept;

DEPTNO dname LOC
---------- -------------- -------------
Ten ACCOUNTING NEW YORK
DALLAS
SALES CHICAGO
OPERATIONS BOSTON

sql> Col deptno format 9999;
Sql> select * FROM dept;

DEPTNO dname LOC
------ -------------- -------------
Ten ACCOUNTING NEW YORK
DALLAS
SALES CHICAGO
OPERATIONS BOSTON

Sets the width of the varchar2 type column here A30 represents a width of 30 characters.

sql> Col dname format A30;
Sql> select * FROM dept;

DEPTNO dname LOC
------ ------------------------------ -------------
Ten ACCOUNTING NEW YORK
DALLAS
SALES CHICAGO
OPERATIONS BOSTON

View Table Structure Decribe tablename

Sql> Select table_name from User_tables;

table_name
------------------------------
DEPT
Emp
BONUS
Salgrade

Sql> describe dept;
 Name        null?    Type
 ----------------- ------------------------------------------------------------
 deptno         Not NULL number (2)
 DNAME          VARCHAR2
 LOC          VARCHAR2 (+)

Sql> describe EMP;
 Name        null?    Type
 ----------------- ------------------------------------------------------------
 EMPNO         not NULL number (4)
 ENAME          VARCHAR2 (10)
 JOB          VARCHAR2 (9)
 MGR           Number (4)
 HIREDATE          DATE
 SAL          number (7,2)
 COMM           number (7,2)
 deptno           Number (2)

sql> describe bonus;
Name Null? Type
----------------------------------------- -------- ----------------------------
Ename VARCHAR2 (10)
JOB VARCHAR2 (9)
SAL number
COMM number

Sql> describe Salgrade;
Name Null? Type
----------------------------------------- -------- ----------------------------
GRADE number
Losal number
Hisal number

Oracle queries all tables and sqlplus in the current user to set the column width