Section B.2. Formatting Character Strings

B 2 Formatting Character Strings

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.