SQL*Plus

Use &tspace or &&tspace to reference this variable in your SQLData type can be CHAR, NUMBER or DATEYou can specify a FORMAT. Entries that don't match the FORMAT spec will be rejected.You can specify a DEFAULT which will take effect if the user presses Enter without entering any other characters.You can HIDE the user's response (useful for passwords).If you specify NOMPROMPT instead of PROMPT then no prompt will be shown (useful if you have already prompted using standalone PROMPT commands.

BREAK

BREAK ON tablespace SKIP 1

COMPUTE

COMPUTE SUM LABEL 'total_mb' OF size_mb ON tablespace

COLUMN

COLUMN querycol FORMAT a30

PROMPT

PROMPT The line above shows a blank line. This line shows this text

PROMPT The next line shows the current value of the tspace variable

PROMPT &tspace

SET

TODO

SET VERIFY OFF

SET HEADING OFF

SET PAGESIZE 99

SET LINESIZE 99

SET FEEDBACK OFF

SET TRIMSPOOL ON

SET SERVEROUTPUT ON

Bibliography

https://blogs.oracle.com/opal/sqlplus-101-substitution-variables https://docs.oracle.com/cd/B19306_01/server.102/b14357/ch12014.htm (COMPUTE)https://docs.oracle.com/cd/B19306_01/server.102/b14357/ch12013.htm (COLUMN)https://www.oreilly.com/library/view/oracle-sqlplus-the/1565925785/ch04s03.html
SEThttps://stackoverflow.com/questions/5340716/suppress-output-of-variables-substitution-in-sqlplus
Defaultshttps://www.funoracleapps.com/2020/11/sqlplus-prompt-with-gloginsql-and.html