extract operator: add support for week keywords (#436)

Author: Ted-Jiang

src/ast/value.rs

@@ -123,6 +123,7 @@ impl fmt::Display for Value {
 pub enum DateTimeField {
     Year,
     Month,
+    Week,
     Day,
     Hour,
     Minute,
@@ -149,6 +150,7 @@ impl fmt::Display for DateTimeField {
         f.write_str(match self {
             DateTimeField::Year => "YEAR",
             DateTimeField::Month => "MONTH",
+            DateTimeField::Week => "WEEK",
             DateTimeField::Day => "DAY",
             DateTimeField::Hour => "HOUR",
             DateTimeField::Minute => "MINUTE",

src/keywords.rs

@@ -518,6 +518,7 @@ define_keywords!(
     VERSIONING,
     VIEW,
     VIRTUAL,
+    WEEK,
     WHEN,
     WHENEVER,
     WHERE,

src/parser.rs

@@ -909,6 +909,7 @@ impl<'a> Parser<'a> {
             Token::Word(w) => match w.keyword {
                 Keyword::YEAR => Ok(DateTimeField::Year),
                 Keyword::MONTH => Ok(DateTimeField::Month),
+                Keyword::WEEK => Ok(DateTimeField::Week),
                 Keyword::DAY => Ok(DateTimeField::Day),
                 Keyword::HOUR => Ok(DateTimeField::Hour),
                 Keyword::MINUTE => Ok(DateTimeField::Minute),
@@ -966,6 +967,7 @@ impl<'a> Parser<'a> {
                 if [
                     Keyword::YEAR,
                     Keyword::MONTH,
+                    Keyword::WEEK,
                     Keyword::DAY,
                     Keyword::HOUR,
                     Keyword::MINUTE,

tests/sqlparser_common.rs

@@ -1384,6 +1384,7 @@ fn parse_extract() {
     one_statement_parses_to("SELECT EXTRACT(year from d)", "SELECT EXTRACT(YEAR FROM d)");
 
     verified_stmt("SELECT EXTRACT(MONTH FROM d)");
+    verified_stmt("SELECT EXTRACT(WEEK FROM d)");
     verified_stmt("SELECT EXTRACT(DAY FROM d)");
     verified_stmt("SELECT EXTRACT(HOUR FROM d)");
     verified_stmt("SELECT EXTRACT(MINUTE FROM d)");