Query Your Data with SQL

Register data files as named sources, then query them with full SQL. Sources are persisted in the catalog and survive session restarts.

Register a source

Rust

#![allow(unused)]
fn main() {
extern crate jammi_db;
extern crate jammi_ai;
extern crate tokio;
use jammi_ai::session::InferenceSession;
async fn ex(session: &InferenceSession) -> jammi_db::error::Result<()> {
use jammi_db::source::{FileFormat, SourceConnection, SourceType};

session.add_source("patents", SourceType::File, SourceConnection {
    url: Some("file:///data/patents.parquet".into()),
    format: Some(FileFormat::Parquet),
    ..Default::default()
}).await?;
Ok(()) }
}

Python

db.add_source("patents", path="/data/patents.parquet", format="parquet")

CLI

jammi sources add patents --path /data/patents.parquet --format parquet

Supported formats

Run a SQL query

Sources are accessible via three-part SQL names: <source_id>.public.<table_name>. The table name is derived from the file name (e.g., patents.parquet becomes patents).

Rust

#![allow(unused)]
fn main() {
extern crate jammi_db;
extern crate jammi_ai;
extern crate tokio;
use jammi_ai::session::InferenceSession;
async fn ex(session: &InferenceSession) -> jammi_db::error::Result<()> {
let results = session.sql(
    "SELECT id, title, year FROM patents.public.patents WHERE year > 2020 ORDER BY year"
).await?;

for batch in &results {
    println!("{batch:?}");
}
Ok(()) }
}

Python

table = db.sql("SELECT id, title, year FROM patents.public.patents WHERE year > 2020 ORDER BY year")
print(table.to_pandas())

CLI

jammi query "SELECT id, title, year FROM patents.public.patents WHERE year > 2020 ORDER BY year"

Aggregations

SELECT category, COUNT(*) as count, AVG(citation_count) as avg_citations
FROM patents.public.patents
WHERE year > 2020
GROUP BY category
ORDER BY count DESC

Joins across sources

Register multiple sources and join them in a single query:

Rust

#![allow(unused)]
fn main() {
extern crate jammi_db;
extern crate jammi_ai;
extern crate tokio;
use jammi_ai::session::InferenceSession;
use jammi_db::source::{FileFormat, SourceConnection, SourceType};
async fn ex(session: &InferenceSession) -> jammi_db::error::Result<()> {
session.add_source("companies", SourceType::File, SourceConnection {
    url: Some("file:///data/companies.csv".into()),
    format: Some(FileFormat::Csv),
    ..Default::default()
}).await?;

let results = session.sql("
    SELECT p.title, c.company_name
    FROM patents.public.patents p
    JOIN companies.public.companies c ON p.assignee_id = c.id
").await?;
Ok(()) }
}

Python

db.add_source("companies", path="/data/companies.csv", format="csv")

table = db.sql("""
    SELECT p.title, c.company_name
    FROM patents.public.patents p
    JOIN companies.public.companies c ON p.assignee_id = c.id
""")

Source lifecycle

Rust

#![allow(unused)]
fn main() {
extern crate jammi_db;
extern crate jammi_ai;
extern crate tokio;
use jammi_ai::session::InferenceSession;
async fn ex(session: &InferenceSession) -> jammi_db::error::Result<()> {
// List registered sources
let sources = session.catalog().list_sources().await?;

// Remove a source
session.remove_source("patents").await?;
Ok(()) }
}

CLI

jammi sources list

Sources persist in the SQLite catalog at <artifact_dir>/catalog.db. Registering the same source ID twice returns an error — remove it first.

Execution plans

Use EXPLAIN (or the CLI explain command) to see how DataFusion will execute your query:

jammi explain "SELECT * FROM patents.public.patents WHERE year > 2020"