Feat/movie example (#307)

# Rationale for this change

Add an additional movies example to help improve documentation.

# What changes are included in this PR?

movies example is added.

# Are these changes tested?
No

crates/proof-of-sql/Cargo.toml

@@ -103,6 +103,10 @@ required-features = [ "arrow" ]
 name = "wood_types"
 required-features = [ "arrow" ]
 
+[[example]]
+name = "movies"
+required-features = [ "arrow" ]
+
 [[example]]
 name = "dinosaurs"
 required-features = [ "arrow" ]

crates/proof-of-sql/examples/movies/main.rs

@@ -0,0 +1,120 @@
+//! This is a non-interactive example of using Proof of SQL with a movies dataset.
+//! To run this, use `cargo run --release --example movies`.
+//!
+//! NOTE: If this doesn't work because you do not have the appropriate GPU drivers installed,
+//! you can run `cargo run --release --example movies --no-default-features --features="arrow cpu-perf"` instead. It will be slower for proof generation.
+
+use arrow::datatypes::SchemaRef;
+use arrow_csv::{infer_schema_from_files, ReaderBuilder};
+use proof_of_sql::{
+    base::database::{
+        arrow_schema_utility::get_posql_compatible_schema, OwnedTable, OwnedTableTestAccessor,
+        TestAccessor,
+    },
+    proof_primitive::dory::{
+        DynamicDoryCommitment, DynamicDoryEvaluationProof, ProverSetup, PublicParameters,
+        VerifierSetup,
+    },
+    sql::{parse::QueryExpr, postprocessing::apply_postprocessing_steps, proof::QueryProof},
+};
+use rand::{rngs::StdRng, SeedableRng};
+use std::{fs::File, time::Instant};
+
+// We generate the public parameters and the setups used by the prover and verifier for the Dory PCS.
+// The `max_nu` should be set such that the maximum table size is less than `2^(2*max_nu-1)`.
+const DORY_SETUP_MAX_NU: usize = 8;
+// This should be a "nothing-up-my-sleeve" phrase or number.
+const DORY_SEED: [u8; 32] = *b"ebab60d58dee4cc69658939b7c2a582d";
+
+/// # Panics
+/// Will panic if the query does not parse or the proof fails to verify.
+fn prove_and_verify_query(
+    sql: &str,
+    accessor: &OwnedTableTestAccessor<DynamicDoryEvaluationProof>,
+    prover_setup: &ProverSetup,
+    verifier_setup: &VerifierSetup,
+) {
+    // Parse the query:
+    println!("Parsing the query: {sql}...");
+    let now = Instant::now();
+    let query_plan = QueryExpr::<DynamicDoryCommitment>::try_new(
+        sql.parse().unwrap(),
+        "movies".parse().unwrap(),
+        accessor,
+    )
+    .unwrap();
+    println!("Done in {} ms.", now.elapsed().as_secs_f64() * 1000.);
+
+    // Generate the proof and result:
+    print!("Generating proof...");
+    let now = Instant::now();
+    let (proof, provable_result) = QueryProof::<DynamicDoryEvaluationProof>::new(
+        query_plan.proof_expr(),
+        accessor,
+        &prover_setup,
+    );
+    println!("Done in {} ms.", now.elapsed().as_secs_f64() * 1000.);
+
+    // Verify the result with the proof:
+    print!("Verifying proof...");
+    let now = Instant::now();
+    let result = proof
+        .verify(
+            query_plan.proof_expr(),
+            accessor,
+            &provable_result,
+            &verifier_setup,
+        )
+        .unwrap();
+    let result = apply_postprocessing_steps(result.table, query_plan.postprocessing());
+    println!("Verified in {} ms.", now.elapsed().as_secs_f64() * 1000.);
+
+    // Display the result
+    println!("Query Result:");
+    println!("{result:?}");
+}
+
+fn main() {
+    let mut rng = StdRng::from_seed(DORY_SEED);
+    let public_parameters = PublicParameters::rand(DORY_SETUP_MAX_NU, &mut rng);
+    let prover_setup = ProverSetup::from(&public_parameters);
+    let verifier_setup = VerifierSetup::from(&public_parameters);
+
+    let filename = "./crates/proof-of-sql/examples/movies/movies.csv";
+    let inferred_schema =
+        SchemaRef::new(infer_schema_from_files(&[filename.to_string()], b',', None, true).unwrap());
+    let posql_compatible_schema = get_posql_compatible_schema(&inferred_schema);
+
+    let movies_batch = ReaderBuilder::new(posql_compatible_schema)
+        .with_header(true)
+        .build(File::open(filename).unwrap())
+        .unwrap()
+        .next()
+        .unwrap()
+        .unwrap();
+
+    // Load the table into an "Accessor" so that the prover and verifier can access the data/commitments.
+    let mut accessor =
+        OwnedTableTestAccessor::<DynamicDoryEvaluationProof>::new_empty_with_setup(&prover_setup);
+    accessor.add_table(
+        "movies.movies".parse().unwrap(),
+        OwnedTable::try_from(movies_batch).unwrap(),
+        0,
+    );
+
+    // Query 1: Count the total number of movies
+    prove_and_verify_query(
+        "SELECT COUNT(*) AS total_movies FROM movies",
+        &accessor,
+        &prover_setup,
+        &verifier_setup,
+    );
+
+    // Query 2: Find the top 5 highest-rated movies
+    prove_and_verify_query(
+        "SELECT title, rating FROM movies ORDER BY rating DESC LIMIT 5",
+        &accessor,
+        &prover_setup,
+        &verifier_setup,
+    );
+}

crates/proof-of-sql/examples/movies/movies.csv

@@ -0,0 +1,31 @@
+id, title, year, genre, rating, duration
+1, The Matrix, 1999, Action, 8.7, 136
+2, The Matrix Reloaded, 2003, Action, 7.2, 138
+3, The Matrix Revolutions, 2003, Action, 6.7, 129
+4, Inception, 2010, Sci-Fi, 8.8, 148
+5, The Dark Knight, 2008, Action, 9.0, 152
+6, Pulp Fiction, 1994, Crime, 8.9, 154
+7, Forrest Gump, 1994, Drama, 8.8, 142
+8, The Shawshank Redemption, 1994, Drama, 9.3, 142
+9, The Godfather, 1972, Crime, 9.2, 175
+10, Fight Club, 1999, Drama, 8.8, 139
+11, The Lord of the Rings: The Fellowship of the Ring, 2001, Adventure, 8.8, 178
+12, Goodfellas, 1990, Crime, 8.7, 146
+13, The Silence of the Lambs, 1991, Thriller, 8.6, 118
+14, Schindler's List, 1993, Biography, 8.9, 195
+15, Interstellar, 2014, Sci-Fi, 8.6, 169
+16, The Green Mile, 1999, Crime, 8.6, 189
+17, Saving Private Ryan, 1998, War, 8.6, 169
+18, Gladiator, 2000, Action, 8.5, 155
+19, The Avengers, 2012, Action, 8.0, 143
+20, Jurassic Park, 1993, Adventure, 8.1, 127
+21, The Lion King, 1994, Animation, 8.5, 88
+22, Titanic, 1997, Romance, 7.8, 194
+23, The Departed, 2006, Crime, 8.5, 151
+24, The Prestige, 2006, Mystery, 8.5, 130
+25, The Social Network, 2010, Biography, 7.7, 120
+26, Avatar, 2009, Action, 7.8, 162
+27, The Sixth Sense, 1999, Thriller, 8.1, 107
+28, The Usual Suspects, 1995, Crime, 8.5, 106
+29, Memento, 2000, Mystery, 8.4, 113
+30, Eternal Sunshine of the Spotless Mind, 2004, Romance, 8.3, 108