Implement field selection in the MySQL library.

module/Library/MySQL.cpp

@@ -2652,6 +2652,30 @@ Array ResultSet::GetFieldsArray() const
     return arr;
 }
 
+// ------------------------------------------------------------------------------------------------
+Array ResultSet::FetchFieldsArray(Array & fields) const
+{
+    SQMOD_VALIDATE_CREATED(*this);
+    // Is there even something to process?
+    if (!m_Handle->mFieldCount || fields.Length() == 0)
+    {
+        return Array(DefaultVM::Get(), 0);
+    }
+    // Create a field instance to insert as copy
+    Field field(m_Handle);
+    // Allocate an array with the same amount of elements as the number of fields
+    Array arr(DefaultVM::Get(), fields.Length());
+	// Iterate the specified fields array
+	fields.Foreach([&field, &arr](HSQUIRRELVM vm, SQInteger i) -> SQRESULT {
+        // Update the field index
+        field.SetIndex(Object(-1, vm));
+        // Insert a copy of the field instance into the array
+        arr.SetValue(i, field);
+	});
+    // Return the resulted array
+    return arr;
+}
+
 // ------------------------------------------------------------------------------------------------
 Table ResultSet::GetFieldsTable() const
 {
@@ -2681,6 +2705,32 @@ Table ResultSet::GetFieldsTable() const
     return tbl;
 }
 
+// ------------------------------------------------------------------------------------------------
+Table ResultSet::FetchFieldsTable(Array & fields) const
+{
+    SQMOD_VALIDATE_CREATED(*this);
+    // Is there even something to process?
+    if (!m_Handle->mFieldCount || fields.Length() == 0)
+    {
+        return Table();
+    }
+    // Create a field instance to insert as copy
+    Field field(m_Handle);
+    // Allocate a table to be populated with field instances
+    Table tbl(DefaultVM::Get(), fields.Length());
+    // Grab the array with field instances
+    const ResHnd::FieldType * pfields = m_Handle->mFields;
+	// Iterate the specified fields array
+	fields.Foreach([&field, &tbl, pfields](HSQUIRRELVM vm, SQInteger i) -> SQRESULT {
+        // Update the field index
+        field.SetIndex(Object(-1, vm));
+        // Insert a copy of the field instance into the table
+        tbl.SetValue((pfields[field.GetIndex()].name == nullptr) ? ToStrF("<field_%ld>", field.GetIndex()) : pfields[field.GetIndex()].name, field);
+	});
+    // Return the resulted array
+    return tbl;
+}
+
 // ------------------------------------------------------------------------------------------------
 SQInteger Statement::Typename(HSQUIRRELVM vm)
 {
@@ -3254,6 +3304,8 @@ void Register_MySQL(HSQUIRRELVM vm)
         .Func(_SC("GetString"), &ResultSet::GetString)
         .Func(_SC("GetBuffer"), &ResultSet::GetBuffer)
         .Func(_SC("GetBlob"), &ResultSet::GetBlob)
+        .Func(_SC("GetFieldsArray"), &ResultSet::FetchFieldsArray)
+        .Func(_SC("GetFieldsTable"), &ResultSet::FetchFieldsTable)
     );
 
     sqlns.Bind(_SC("Statement")

module/Library/MySQL.hpp

@@ -2082,11 +2082,21 @@ public:
     */
     Array GetFieldsArray() const;
 
+    /* --------------------------------------------------------------------------------------------
+     * Returns an array with wrapper instances for the specified fields in the managed result set.
+    */
+    Array FetchFieldsArray(Array & fields) const;
+
     /* --------------------------------------------------------------------------------------------
      * Returns a table with wrapper instances for all the field available in the managed result set.
     */
     Table GetFieldsTable() const;
 
+    /* --------------------------------------------------------------------------------------------
+     * Returns a table with wrapper instances for all the specified fields in the managed result set.
+    */
+    Table FetchFieldsTable(Array & fields) const;
+
     /* --------------------------------------------------------------------------------------------
      * Returns the current position of the row cursor for the last Next().
     */

module/Misc/Areas.cpp

@@ -20,7 +20,7 @@ void Area::AddArray(const Sqrat::Array & a)
 {
     float values[2];
 
-    a.Foreach([this, &values, n = int(0)](HSQUIRRELVM vm) mutable -> bool {
+    a.Foreach([this, &values, n = int(0)](HSQUIRRELVM vm, SQInteger i) mutable -> SQRESULT {
         // Retrieve the type of the value
         const SQObjectType type = sq_gettype(vm, -1);
         // Are we dealing with a vector?
@@ -44,7 +44,7 @@ void Area::AddArray(const Sqrat::Array & a)
             }
         }
         // Ignore anything else
-        return true;
+        return SQ_OK;
     });
 }
 #pragma clang diagnostic pop

sqrat/sqrat/sqratObject.h

@@ -540,19 +540,22 @@ public:
     ///
     /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
     template<class F>
-    void Foreach(F&& func) const
+    SQRESULT Foreach(F&& func) const
     {
         const StackGuard sg(vm);
         sq_pushobject(vm,obj);
         sq_pushnull(vm);
-        while(SQ_SUCCEEDED(sq_next(vm,-2)))
+		SQRESULT res = SQ_OK;
+        for(SQInteger i = 0; SQ_SUCCEEDED(sq_next(vm,-2)); ++i)
         {
-            if (!func(vm))
+			res = func(vm, i);
+            if (SQ_FAILED(res))
             {
-                return;
+                break;
             }
             sq_pop(vm,2);
         }
+		return res;
     }
 
 protected: