feat(wire): honor binary result-format codes on the live-data path

Power BI Desktop / Tableau and other Npgsql/pgjdbc clients bind result
columns for binary in the extended-query protocol, but the gateway emitted
text-format DataRows unconditionally. Binary-decoding text bytes fails for
every type except varchar (whose binary and text wire forms are identical),
which surfaced as "ERROR on Float/Integer/Timestamp columns, strings fine"
in the Power BI Navigator preview while the full (text) data load worked.
Real PostgreSQL honors the Bind request and sends binary, which was the one
concrete behavioural difference.

Honor the portal's `result_column_format` on the live-data path:

- `types::encode_cell` dispatches per-column on the requested `FieldFormat`
  and converts Trino JSON values to typed Rust values so pgwire's
  `DataRowEncoder` emits PostgreSQL binary: bool, int2/4/8, float4/8,
  numeric, date, time, timestamp (without tz); the string family passes
  through as bytes (binary == text). Unsupported types fail closed
  (SQLSTATE 0A000) rather than emit bytes the client would misread; SQL
  NULL is handled once (format-independent -1 length).
- `trino_stream::build_pg_schema` sets each column's format from the portal,
  threaded through `process_query` -> `execute_trino_query`. The simple-query
  path stays text (it never negotiates binary).

The static catalog/intercept path remains text-only (type-loading drivers
request text there); tracked as follow-up.

Tests:
- Byte-level unit tests for `encode_cell` in `types.rs` (no Trino).
- The three extended-protocol tests that were `#[ignore]`'d for this are
  re-enabled, plus a new test covering the customer's exact column types
  (bigint, real, double, timestamp). Verified end-to-end against Trino 479:
  they pass with the fix and fail with "error deserializing column" when the
  schema-format line is reverted.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: lfrancke

Cargo.lock

@@ -28,12 +28,21 @@ sqlparser = { version = "0.61", features = ["visitor"] }
 # around this same code.
 rustls-pki-types = { version = "1", features = ["std"] }
 rand = "0.10"
+# Used to build typed values for the binary result-wire-format path
+# (`types::encode_cell`). Versions are unified with the impls pgwire's
+# default features pull into `postgres-types` (chrono 0.4, rust_decimal 1.x
+# with `db-postgres`), so the `ToSql`/`ToSqlText` impls apply.
+chrono = "0.4"
+rust_decimal = { version = "1", features = ["db-postgres"] }
 
 [build-dependencies]
 chrono = "0.4"
 
 [dev-dependencies]
-tokio-postgres = "0.7"
+# with-chrono-0_4 lets the test client decode binary timestamps, exercising
+# the binary result path for the customer's timestamp columns end-to-end.
+tokio-postgres = { version = "0.7", features = ["with-chrono-0_4"] }
+chrono = "0.4"
 tempfile = "3"
 rcgen = "0.14"
 

Cargo.toml

@@ -117,6 +117,7 @@ impl ExtendedQueryHandler for GatewayExtendedQueryHandler {
             &conn_state.trino_client,
             &conn_state.config,
             Some(&conn_state.active_query_id),
+            Some(&portal.result_column_format),
         )
         .await?;
         let response = responses
@@ -190,11 +191,16 @@ impl ExtendedQueryHandler for GatewayExtendedQueryHandler {
         // row-returning query. The result Stream is dropped here; Trino's
         // server-side query state is freed via its own TTL (see TODO in
         // `do_describe_portal` below for promoter cancellation).
+        //
+        // The result format isn't known at Describe-Statement time (no Bind
+        // yet), so the RowDescription is built as text; the actual per-column
+        // format is applied later in do_query against the bound portal.
         let responses = process_query(
             query,
             &conn_state.trino_client,
             &conn_state.config,
             Some(&conn_state.active_query_id),
+            None,
         )
         .await?;
         let response = responses
@@ -234,6 +240,7 @@ impl ExtendedQueryHandler for GatewayExtendedQueryHandler {
             &conn_state.trino_client,
             &conn_state.config,
             Some(&conn_state.active_query_id),
+            Some(&portal.result_column_format),
         )
         .await?;
         let response = responses

src/query_extended.rs

@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: OSL-3.0
 use std::sync::Arc;
 
+use pgwire::api::portal::Format;
 use pgwire::api::results::{QueryResponse, Response, Tag};
 use pgwire::error::{PgWireError, PgWireResult};
 use sqlparser::dialect::PostgreSqlDialect;
@@ -38,23 +39,37 @@ use crate::trino_stream::execute_trino_query;
 /// returns; cancelling them after later statements have submitted is not
 /// supported, but no documented client (Power BI, pgjdbc) exercises this
 /// path.
+/// `result_format` carries the per-column wire format the client bound for
+/// results (extended-query path); `None` means all-text (simple-query
+/// protocol, which never negotiates binary). It is forwarded to
+/// `execute_trino_query` so the result schema and DataRow encoding honor it.
 pub(crate) async fn process_query(
     query: &str,
     trino_client: &Arc<TrinoClient>,
     config: &Arc<Config>,
     active_query_id: Option<&ActiveQueryId>,
+    result_format: Option<&Format>,
 ) -> PgWireResult<Vec<Response>> {
     tracing::trace!(query, "Pipeline: enter");
 
     let pieces = split_statements(query);
     if pieces.len() <= 1 {
-        return process_single_statement(query, trino_client, config, active_query_id).await;
+        return process_single_statement(
+            query,
+            trino_client,
+            config,
+            active_query_id,
+            result_format,
+        )
+        .await;
     }
 
     tracing::trace!(count = pieces.len(), "Pipeline: multi-statement input");
     let mut out = Vec::with_capacity(pieces.len());
     for stmt in &pieces {
-        match process_single_statement(stmt, trino_client, config, active_query_id).await {
+        match process_single_statement(stmt, trino_client, config, active_query_id, result_format)
+            .await
+        {
             Ok(mut responses) => out.append(&mut responses),
             // User-visible errors (e.g. a Trino syntax error on statement N
             // of a batch) are converted to a Response::Error so that the
@@ -91,6 +106,7 @@ async fn process_single_statement(
     trino_client: &Arc<TrinoClient>,
     config: &Arc<Config>,
     active_query_id: Option<&ActiveQueryId>,
+    result_format: Option<&Format>,
 ) -> PgWireResult<Vec<Response>> {
     // The query is parsed up to three times: once here (for routing
     // checks), once by the multi-statement splitter in the public
@@ -136,7 +152,7 @@ async fn process_single_statement(
     tracing::debug!(original = query, rewritten = %rewritten, "Rewritten query");
 
     let (schema, row_stream) =
-        execute_trino_query(trino_client, rewritten, active_query_id).await?;
+        execute_trino_query(trino_client, rewritten, active_query_id, result_format).await?;
 
     if schema.is_empty() {
         tracing::trace!("Pipeline: Trino returned no schema — treating as DDL/DML");

src/query_pipeline.rs

@@ -31,11 +31,14 @@ impl SimpleQueryHandler for GatewayQueryHandler {
             .get::<ConnectionState>()
             .ok_or_else(|| PgWireError::ApiError("Connection state not found".into()))?;
 
+        // The simple-query protocol always uses text wire format; it never
+        // negotiates per-column binary results.
         let result = process_query(
             query,
             &conn_state.trino_client,
             &conn_state.config,
             Some(&conn_state.active_query_id),
+            None,
         )
         .await;
         match &result {

src/query_simple.rs

@@ -4,6 +4,7 @@ use std::sync::Arc;
 
 use async_stream::stream;
 use futures::Stream;
+use pgwire::api::portal::Format;
 use pgwire::api::results::{DataRowEncoder, FieldFormat, FieldInfo};
 use pgwire::error::{PgWireError, PgWireResult};
 use pgwire::messages::data::DataRow;
@@ -12,7 +13,7 @@ use trino_rust_client::models::{Column, QueryResultData};
 use trino_rust_client::{Client, Row};
 
 use crate::session::ActiveQueryId;
-use crate::types::{encode_value, trino_type_to_pg};
+use crate::types::{encode_cell, trino_type_to_pg};
 
 #[derive(Clone)]
 pub(crate) struct TrinoColumn {
@@ -29,17 +30,29 @@ impl From<&Column> for TrinoColumn {
     }
 }
 
-pub(crate) fn build_pg_schema(columns: &[TrinoColumn]) -> Arc<Vec<FieldInfo>> {
+/// Build the PG `RowDescription` schema for a Trino result set.
+///
+/// `result_format` is the per-column format the client bound for results;
+/// `None` means all-text (the simple-query protocol, which never negotiates
+/// binary). Each column's `FieldFormat` is taken from that request, so the
+/// schema drives both the advertised RowDescription and the per-cell encoding
+/// in `encode_row` — keeping them in lock-step.
+pub(crate) fn build_pg_schema(
+    columns: &[TrinoColumn],
+    result_format: Option<&Format>,
+) -> Arc<Vec<FieldInfo>> {
     Arc::new(
         columns
             .iter()
-            .map(|col| {
+            .enumerate()
+            .map(|(idx, col)| {
+                let format = result_format.map_or(FieldFormat::Text, |f| f.format_for(idx));
                 FieldInfo::new(
                     col.name.clone(),
                     None,
                     None,
                     trino_type_to_pg(&col.trino_type),
-                    FieldFormat::Text,
+                    format,
                 )
             })
             .collect(),
@@ -52,8 +65,15 @@ pub(crate) fn encode_row(
     schema: &Arc<Vec<FieldInfo>>,
 ) -> PgWireResult<DataRow> {
     let mut encoder = DataRowEncoder::new(schema.clone());
-    for (value, col) in values.iter().zip(columns.iter()) {
-        encoder.encode_field(&encode_value(value, &col.trino_type))?;
+    for (idx, (value, col)) in values.iter().zip(columns.iter()).enumerate() {
+        let field = &schema[idx];
+        encode_cell(
+            &mut encoder,
+            value,
+            field.datatype(),
+            &col.trino_type,
+            field.format(),
+        )?;
     }
     Ok(encoder.take_row())
 }
@@ -126,6 +146,7 @@ pub async fn execute_trino_query(
     client: &Arc<Client>,
     sql: String,
     active_query_id: Option<&ActiveQueryId>,
+    result_format: Option<&Format>,
 ) -> Result<
     (
         Arc<Vec<FieldInfo>>,
@@ -200,7 +221,7 @@ pub async fn execute_trino_query(
 
     // Empty schema means DDL/DML; the caller returns Response::Execution
     // instead of Response::Query.
-    let schema = build_pg_schema(&trino_columns);
+    let schema = build_pg_schema(&trino_columns, result_format);
 
     let stream_client = Arc::clone(client);
     let stream_columns = trino_columns.clone();
@@ -298,7 +319,7 @@ mod tests {
                 trino_type: "varchar".to_owned(),
             },
         ];
-        let schema = build_pg_schema(&columns);
+        let schema = build_pg_schema(&columns, None);
         assert_eq!(schema.len(), 2);
         assert_eq!(schema[0].name(), "id");
         assert_eq!(*schema[0].datatype(), Type::INT4);
@@ -318,7 +339,7 @@ mod tests {
                 trino_type: "varchar".to_owned(),
             },
         ];
-        let schema = build_pg_schema(&columns);
+        let schema = build_pg_schema(&columns, None);
         let values = vec![json!(42), json!("alice")];
 
         let row = encode_row(&values, &columns, &schema);
@@ -331,7 +352,7 @@ mod tests {
             name: "val".to_owned(),
             trino_type: "varchar".to_owned(),
         }];
-        let schema = build_pg_schema(&columns);
+        let schema = build_pg_schema(&columns, None);
         let values = vec![Value::Null];
 
         let row = encode_row(&values, &columns, &schema);