fix: only require DESCRIBE TABLE for Snowflake and ClickHouse dialect (#1386)

src/dialect/clickhouse.rs

@@ -33,4 +33,8 @@ impl Dialect for ClickHouseDialect {
     fn supports_select_wildcard_except(&self) -> bool {
         true
     }
+
+    fn describe_requires_table_keyword(&self) -> bool {
+        true
+    }
 }

src/dialect/mod.rs

@@ -485,9 +485,20 @@ pub trait Dialect: Debug + Any {
         }
     }
 
+    /// Returns the precedence when the precedence is otherwise unknown
     fn prec_unknown(&self) -> u8 {
         0
     }
+
+    /// Returns true if this dialect requires the `TABLE` keyword after `DESCRIBE`
+    ///
+    /// Defaults to false.
+    ///
+    /// If true, the following statement is valid: `DESCRIBE TABLE my_table`
+    /// If false, the following statements are valid: `DESCRIBE my_table` and `DESCRIBE table`
+    fn describe_requires_table_keyword(&self) -> bool {
+        false
+    }
 }
 
 /// This represents the operators for which precedence must be defined

src/dialect/snowflake.rs

@@ -154,6 +154,10 @@ impl Dialect for SnowflakeDialect {
             _ => None,
         }
     }
+
+    fn describe_requires_table_keyword(&self) -> bool {
+        true
+    }
 }
 
 /// Parse snowflake create table statement.

src/parser/mod.rs

@@ -8185,15 +8185,20 @@ impl<'a> Parser<'a> {
                 format,
             }),
             _ => {
-                let mut hive_format = None;
-                match self.parse_one_of_keywords(&[Keyword::EXTENDED, Keyword::FORMATTED]) {
-                    Some(Keyword::EXTENDED) => hive_format = Some(HiveDescribeFormat::Extended),
-                    Some(Keyword::FORMATTED) => hive_format = Some(HiveDescribeFormat::Formatted),
-                    _ => {}
-                }
+                let hive_format =
+                    match self.parse_one_of_keywords(&[Keyword::EXTENDED, Keyword::FORMATTED]) {
+                        Some(Keyword::EXTENDED) => Some(HiveDescribeFormat::Extended),
+                        Some(Keyword::FORMATTED) => Some(HiveDescribeFormat::Formatted),
+                        _ => None,
+                    };
+
+                let has_table_keyword = if self.dialect.describe_requires_table_keyword() {
+                    // only allow to use TABLE keyword for DESC|DESCRIBE statement
+                    self.parse_keyword(Keyword::TABLE)
+                } else {
+                    false
+                };
 
-                // only allow to use TABLE keyword for DESC|DESCRIBE statement
-                let has_table_keyword = self.parse_keyword(Keyword::TABLE);
                 let table_name = self.parse_object_name(false)?;
                 Ok(Statement::ExplainTable {
                     describe_alias,