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File Storage

File Storage is a simple persistent storage backend that writes data to the local filesystem. For each table a schema file is written as TABLE_NAME.sql using the original CREATE TABLE statement. Every inserted row is stored as an individual RON file in a directory with the same name as the table.

This storage is useful when you need lightweight persistence without running a database server. Because it relies on the filesystem, it is available only for Rust targets that have std::fs access.

Setup​

Add gluesql-file-storage to your Cargo.toml and create the storage by specifying a path where files should be stored:

[dependencies]
gluesql-file-storage = "*"
use gluesql::prelude::Glue;
use gluesql_file_storage::FileStorage;

let storage = FileStorage::new("./data").unwrap();
let mut glue = Glue::new(storage);

Basic Usage​

Once the storage is created you can use normal SQL statements. Below is a short example showing table creation, inserting data and querying it back:

use gluesql::prelude::Value::I64;

glue.execute(
    "CREATE TABLE Todo (id INTEGER, task TEXT);"
).await.unwrap();

glue.execute(
    "INSERT INTO Todo VALUES (1, 'write docs'), (2, 'run tests');"
).await.unwrap();

let result = glue.execute("SELECT * FROM Todo;").await.unwrap();

After running these commands the directory structure under ./data will look similar to:

./data/
├── Todo.sql
└── Todo/
    ├── <uuid1>.ron
    └── <uuid2>.ron

Each .ron file contains the serialized row together with its key.

Limitations​

  • Transaction and index related features are not implemented.
  • Every row is saved as a separate file, so it may not scale well for very large datasets or heavy concurrent workloads.
  • This storage backend only works in environments that provide filesystem access.