Snowflake: parse SHOW [TERSE] UNIQUE KEYS

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: hovaesco

src/ast/mod.rs

@@ -2554,6 +2554,8 @@ pub enum ShowKeysKind {
     Imported,
     /// `SHOW EXPORTED KEYS`
     Exported,
+    /// `SHOW [TERSE] UNIQUE KEYS`
+    Unique,
 }
 
 impl fmt::Display for ShowKeysKind {
@@ -2562,6 +2564,7 @@ impl fmt::Display for ShowKeysKind {
             ShowKeysKind::Primary => f.write_str("PRIMARY"),
             ShowKeysKind::Imported => f.write_str("IMPORTED"),
             ShowKeysKind::Exported => f.write_str("EXPORTED"),
+            ShowKeysKind::Unique => f.write_str("UNIQUE"),
         }
     }
 }

src/dialect/snowflake.rs

@@ -665,6 +665,9 @@ impl Dialect for SnowflakeDialect {
             if parser.parse_keyword(Keyword::EXPORTED) {
                 return Some(parse_show_keys(ShowKeysKind::Exported, terse, parser));
             }
+            if parser.parse_keyword(Keyword::UNIQUE) {
+                return Some(parse_show_keys(ShowKeysKind::Unique, terse, parser));
+            }
             if parser.parse_keywords(&[Keyword::ROW, Keyword::ACCESS, Keyword::POLICIES]) {
                 return Some(parse_show_row_access_policies(parser));
             }