refactor: rename return_reasons.dst to return_reasons_trino.dst

Pair the inherited Java/Trino distribution with the corrected C variant
so both filenames advertise their compat mode at a glance:

    return_reasons_trino.dst   <-- old return_reasons.dst (carries the
                                   "reason 30 missing, reason 31
                                   duplicated" bug, kept for byte-for-byte
                                   Trino fixture stability)
    return_reasons_c.dst       <-- corrected, used by --compat c

Updates the embedded_data.rs lookup table, the distribution loader,
and the doc-comment references in scaling.rs.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: alamb

tpcdsgen/data/return_reasons.dst tpcdsgen/data/return_reasons_trino.dsttpcdsgen/data/return_reasons.dst renamed to tpcdsgen/data/return_reasons_trino.dst

@@ -5,10 +5,10 @@ use crate::types::Date;
 
 /// Row count for the `reason` table under C dsdgen compatibility.
 ///
-/// C dsdgen generates all 75 entries from `return_reasons.dst` at every scale
-/// factor. The Java/Trino port incorrectly used a logarithmic scaling model
-/// starting at 35 for SF1; this constant fixes that when `CompatMode::C` is
-/// active.
+/// C dsdgen generates all 75 entries from `return_reasons_c.dst` at every
+/// scale factor. The Java/Trino port incorrectly used a logarithmic scaling
+/// model starting at 35 for SF1; this constant fixes that when
+/// `CompatMode::C` is active.
 const REASON_ROW_COUNT_C: i64 = 75;
 
 #[derive(Debug, Clone)]
@@ -50,7 +50,7 @@ impl Scaling {
 
         // In C compat mode the reason table is static at 75 rows regardless of scale.
         // The Java port's logarithmic model (35 at SF1) is wrong; C always emits all
-        // 75 entries from return_reasons.dst.
+        // 75 entries from return_reasons_c.dst.
         if table == Table::Reason && self.compat_mode == CompatMode::C {
             return REASON_ROW_COUNT_C;
         }

tpcdsgen/src/config/scaling.rs

@@ -46,7 +46,7 @@ pub fn get_embedded_distribution(filename: &str) -> Option<&'static [u8]> {
         "nouns.dst" => Some(include_bytes!("../../data/nouns.dst")),
         "prepositions.dst" => Some(include_bytes!("../../data/prepositions.dst")),
         "purchase_band.dst" => Some(include_bytes!("../../data/purchase_band.dst")),
-        "return_reasons.dst" => Some(include_bytes!("../../data/return_reasons.dst")),
+        "return_reasons_trino.dst" => Some(include_bytes!("../../data/return_reasons_trino.dst")),
         "return_reasons_c.dst" => Some(include_bytes!("../../data/return_reasons_c.dst")),
         "salutations.dst" => Some(include_bytes!("../../data/salutations.dst")),
         "sentences.dst" => Some(include_bytes!("../../data/sentences.dst")),

tpcdsgen/src/distribution/embedded_data.rs

@@ -11,11 +11,11 @@ impl ReturnReasonsDistribution {
         static DISTRIBUTION: OnceLock<FileBasedStringValuesDistribution> = OnceLock::new();
         DISTRIBUTION.get_or_init(|| {
             FileBasedStringValuesDistribution::build_string_values_distribution(
-                "return_reasons.dst",
+                "return_reasons_trino.dst",
                 1,
                 6,
             )
-            .expect("Failed to load return_reasons.dst")
+            .expect("Failed to load return_reasons_trino.dst")
         })
     }