allow more complex expressions in extract clause

Author: wumpz

src/main/javacc/net/sf/jsqlparser/parser/JSqlParserCC.jj

@@ -1555,7 +1555,7 @@ ExtractExpression ExtractExpression() :
 	"(" 
 		token=<S_IDENTIFIER> { retval.setName(token.image); } 
 		<K_FROM> 
-		expr=PrimaryExpression() { retval.setExpression(expr); }
+		expr=SimpleExpression() { retval.setExpression(expr); }
 	")"
 	{
 		return retval;

src/test/java/net/sf/jsqlparser/test/select/SelectTest.java

@@ -763,6 +763,16 @@ public void testExtractFrom2() throws JSQLParserException {
 		String stmt = "SELECT EXTRACT(year FROM now()) FROM testtable";
 		assertSqlCanBeParsedAndDeparsed(stmt);
 	}
+	
+	public void testExtractFrom3() throws JSQLParserException {
+		String stmt = "SELECT EXTRACT(year FROM (now() - 2)) FROM testtable";
+		assertSqlCanBeParsedAndDeparsed(stmt);
+	}
+	
+	public void testExtractFrom4() throws JSQLParserException {
+		String stmt = "SELECT EXTRACT(minutes FROM now() - '01:22:00') FROM testtable";
+		assertSqlCanBeParsedAndDeparsed(stmt);
+	}
 
 	public void testProblemFunction() throws JSQLParserException {
 		String stmt = "SELECT test() FROM testtable";