- Fix https://stackoverflow.com/questions/60625778/import-complex-xml…

…-from-multiple-files-in-mariadb/60637429#60637429

  Import complex XML from multiple files in MariaDB
  Some row results are missing and replaced by the last file one.
  Thats because Nx and Sx column members are not reset when changing file.
  modified:   storage/connect/tabxml.cpp
  modified:   storage/connect/tabxml.h

storage/connect/tabxml.cpp

@@ -813,12 +813,15 @@ bool TDBXML::Initialize(PGLOBAL g)
   if (Void)
     return false;
 
-  if (Columns && !Bufdone) {
+  if (Columns) {
     // Allocate the buffers that will contain node values
     for (colp = (PXMLCOL)Columns; colp; colp = (PXMLCOL)colp->GetNext())
-      if (!colp->IsSpecial())            // Not a pseudo column
-        if (colp->AllocBuf(g, Mode == MODE_INSERT))
-          return true;
+			if (!colp->IsSpecial()) {            // Not a pseudo column
+				if (!Bufdone && colp->AllocBuf(g, Mode == MODE_INSERT))
+					return true;
+
+				colp->Nx = colp->Sx = -1;
+			} // endif Special
 
     Bufdone = true;
     } // endif Bufdone

storage/connect/tabxml.h

@@ -157,6 +157,7 @@ class DllExport TDBXML : public TDBASE {
 /*  Class XMLCOL: XDB table access method column descriptor.           */
 /***********************************************************************/
 class XMLCOL : public COLBLK {
+	friend class TDBXML;
  public:
   // Constructors
   XMLCOL(PCOLDEF cdp, PTDB tdbp, PCOL cprec, int i, PCSZ am = "XML");