SQL*Plus offers only one format element when it comes to character strings: A. A is always followed by a number specifying the column width in characters . Character strings shorter than the column width are displayed as left-justified within the column. Character strings that exceed the column width are wrapped or truncated based on the option specified in the COLUMN command. The following example shows a text column formatted wide enough to display the entire character string:
SQL> COLUMN a FORMAT A40 SQL> SELECT 'An apple a day keeps the doctor away.' A 2 FROM dual; A ---------------------------------------- An apple a day keeps the doctor away.
You can format the column so it is 18 characters wide, which results in the text being wrapped within that space:
SQL> COLUMN a FORMAT A18 SQL> SELECT 'An apple a day keeps the doctor away.' A 2 FROM dual; A ------------------ An apple a day kee ps the doctor away .
By default, SQL*Plus wraps the text right in the middle of a word if necessary. You can use the WORD_WRAPPED option of the COLUMN command to wrap text only at word boundaries:
SQL> COLUMN a FORMAT A18 WORD_WRAPPED SQL> SELECT 'An apple a day keeps the doctor away.' A 2 FROM dual; A ------------------ An apple a day keeps the doctor away.
You also have the ability to truncate text at the column boundary:
SQL> COLUMN a FORMAT A18 TRUNCATE SQL> SELECT 'An apple a day keeps the doctor away.' A 2 FROM dual; A ------------------ An apple a day kee
When used with the ACCEPT command, a character format defines the maximum number of characters SQL*Plus will accept from the user :
SQL> ACCEPT some_text CHAR FORMAT A10 thisthatthen "thisthatthen" does not match input format "A10" SQL>
Although the character format used with ACCEPT specifies a maximum length, it doesn't specify a minimum length. You can enter fewer characters than the format calls for, even to the point of entering nothing at all.
Introduction to SQL*Plus
A Lightning SQL Tutorial
Generating Reports with SQL*Plus
Creating HTML Reports
Writing SQL*Plus Scripts
Extracting and Loading Data
Exploring Your Database
Tuning and Timing
The Product User Profile
Customizing Your SQL*Plus Environment
Appendix A. SQL*Plus Command Reference
Appendix B. SQL*Plus Format Elements
Oracle SQL*Plus: The Definitive Guide (Definitive Guides)
Authors: Jonathan Gennick
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