The COL command is used in Oracle to change column formatting, including width, header, and alignment. The syntax is: COL
. Format options include: width, header, left/right/center alignment. Other options support wrapping, truncation, even distribution, and wrapping. It should be noted that this command only affects the current session, if the column length exceeds the specified width, the data will be truncated.
Usage of COL in Oracle
The COL command is used to change the column format in the terminal window in Oracle. It allows you to specify column width, header, and alignment.
Usage
<code>COL </code>
Format
## Specify the format of the column, you can Includes the following options:
- Width: Number specifying the width of the column in characters.
- Header: String specifying the column header.
- Alignment: Left (L), right (R) or center (C).
Example
The following example sets the width of column "Employee_Name" to 25 characters, the title "Employee Name", and left alignment:<code>COL Employee_Name FORMAT A25 "Employee Name" LEFT</code>
Additional options
The COL command also supports the following additional options:- NEW_LINE: Inserts a Newline character.
- TRUNC: Truncate data to fit the specified width.
- JUSTIFY: Evenly distribute data among columns.
- WRAPPED: Wrap data to fit the specified width.
Note
- The COL command only affects the current session.
- If the actual length of the column exceeds the specified width, the data will be truncated.
- For long data types (such as CLOB), the COL command only changes the display format without affecting the stored data.
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