file_write
1. FILE_WRITE Function
=======file_write
1. FILE_WRITE Function
>>>>>>> 9d19b1c8cb744c8e86d5c15b74d8b5f719ad62beThe FILE_WRITE function in H2 database is used to write data to a file.
2. Syntax
The syntax for the FILE_WRITE function in H2 database is as follows:
FILE_WRITE(file, data)
Arguments
file
: The name or path of the file to be written. It should be a string (VARCHAR) value.data
: The data to be written to the file. It should be a string (VARCHAR) value.
Return
- The FILE_WRITE function does not return any value.
3. Notes
- The FILE_WRITE function in H2 database allows you to write data to a file on the server-side. It is typically used for file I/O operations within the database.
- The file specified in the
file
argument should either be an absolute path or a path relative to the database server's working directory. - The database user executing the FILE_WRITE function should have appropriate write permissions on the specified file and directory.
- If the file does not exist, it will be created. If the file already exists, the existing content will be overwritten.
- Remember to use the correct syntax and handle file-related errors appropriately while using the FILE_WRITE function.
4. Examples
Here are a few examples demonstrating the usage of the FILE_WRITE function in H2 database:
Example 1 - Writing data to a file:
FILE_WRITE('output.txt', 'Hello, World!');
Output:
The content "Hello, World!" is written to the file output.txt
.
Example 2 - Writing data to a file using a column value:
CREATE TABLE messages (
id INT PRIMARY KEY,
content VARCHAR
);
INSERT INTO messages VALUES (1, 'This is a sample message.');
SELECT id, content, FILE_WRITE('output.txt', content) AS result
FROM messages;
Output: =======
Output:
The content "Hello, World!" is written to the file output.txt
.
Example 2 - Writing data to a file using a column value:
CREATE TABLE messages (
id INT PRIMARY KEY,
content VARCHAR
);
INSERT INTO messages VALUES (1, 'This is a sample message.');
SELECT id, content, FILE_WRITE('output.txt', content) AS result
FROM messages;
Output:
>>>>>>> 9d19b1c8cb744c8e86d5c15b74d8b5f719ad62be
The content of the content
column is written to the file output.txt
, and the result
column will have a NULL
value for each row.
5. Related Functions
- file_read - Read data from a file
- FILE_EXISTS - Check if a file exists