[#1007] Formally document the API methods to indicate whether something is supported by any given SQL dialect

jOOQ-test/src/org/jooq/test/jOOQAbstractTest.java

@@ -1515,13 +1515,14 @@ public abstract class jOOQAbstractTest<
 
     @Test
     public void testLiterals() throws Exception {
-        Record record = create().select(zero(), one(), two(), pi(), e()).fetchOne();
+        Record record = create().select(zero(), one(), two(), pi(), e(), rad(deg(pi()))).fetchOne();
 
         assertEquals(0, record.getValue(0));
         assertEquals(1, record.getValue(1));
         assertEquals(2, record.getValue(2));
         assertEquals("3.141", record.getValueAsString(3).substring(0, 5));
         assertEquals("2.718", record.getValueAsString(4).substring(0, 5));
+        assertEquals("3.141", record.getValueAsString(5).substring(0, 5));
     }
 
     @Test
@@ -6382,6 +6383,12 @@ public abstract class jOOQAbstractTest<
         assertEquals("abc", create().select(trim("abc  ")).fetchOne(0));
         assertEquals("abc", create().select(trim("  abc")).fetchOne(0));
         assertEquals("abc", create().select(trim("  abc  ")).fetchOne(0));
+        assertEquals("  abc", create().select(rtrim("  abc  ")).fetchOne(0));
+        assertEquals("abc  ", create().select(ltrim("  abc  ")).fetchOne(0));
+
+        // Lower / Upper
+        assertEquals("abc", create().select(lower("ABC")).fetchOne(0));
+        assertEquals("ABC", create().select(upper("abc")).fetchOne(0));
 
         // String concatenation
         assertEquals("abc", create().select(concat("a", "b", "c")).fetchOne(0));

jOOQ/src/main/java/org/jooq/FactoryOperations.java

@@ -603,6 +603,7 @@ public interface FactoryOperations extends Configuration {
      * Note, this statement is only supported in DSL mode. Immediate execution
      * is omitted for future extensibility of this command.
      */
+    @Support
     <R extends TableRecord<R>> Truncate<R> truncate(Table<R> table);
 
     // -------------------------------------------------------------------------
@@ -695,6 +696,7 @@ public interface FactoryOperations extends Configuration {
      *
      * @throws DataAccessException if something went wrong executing the query
      */
+    @Support({ DB2, DERBY, H2, HSQLDB, MYSQL, SYBASE, ORACLE, POSTGRES })
     int use(Schema schema) throws DataAccessException;
 
     /**
@@ -703,6 +705,7 @@ public interface FactoryOperations extends Configuration {
      * @see #use(Schema)
      * @throws DataAccessException if something went wrong executing the query
      */
+    @Support({ DB2, DERBY, H2, HSQLDB, MYSQL, SYBASE, ORACLE, POSTGRES })
     int use(String schema) throws DataAccessException;
 
     // -------------------------------------------------------------------------