feat: add COPY TO parquet example with all tables + single udtf

Author: clflushopt

examples/parquet.rs

@@ -0,0 +1,35 @@
+//! Example of using the datafusion-tpch extension to generate TPCH tables
+//! and writing them to disk via `COPY`.
+
+use datafusion::prelude::{SessionConfig, SessionContext};
+use datafusion_tpch::{register_tpch_udtf, register_tpch_udtfs};
+
+#[tokio::main]
+async fn main() -> datafusion::error::Result<()> {
+    let ctx = SessionContext::new_with_config(SessionConfig::new().with_information_schema(true));
+    register_tpch_udtf(&ctx);
+
+    let sql_df = ctx.sql(&format!("SELECT * FROM tpch(1.0);")).await?;
+    sql_df.show().await?;
+
+    let sql_df = ctx.sql(&format!("SHOW TABLES;")).await?;
+    sql_df.show().await?;
+
+    let sql_df = ctx
+        .sql(&format!(
+            "COPY nation TO './tpch_nation.parquet' STORED AS PARQUET"
+        ))
+        .await?;
+    sql_df.show().await?;
+
+    register_tpch_udtfs(&ctx)?;
+
+    let sql_df = ctx
+        .sql(&format!(
+            "COPY (SELECT * FROM tpch_lineitem(1.0)) TO './tpch_lineitem_sf_10.parquet' STORED AS PARQUET"
+        ))
+        .await?;
+    sql_df.show().await?;
+
+    Ok(())
+}