Sanity check: assert that row buffer length is not exceeded at a proper time, instead of dereferencing a broken pointer later on, which has random consequences (given that range checking is off).

components/zeosdbo/src/dbc/ZDbcCache.pas

@@ -231,6 +231,10 @@ begin
     FColumnLengths[I] := GetColumnSize(Current);
     FColumnOffsets[I] := FColumnsSize;
     Inc(FColumnsSize, FColumnLengths[I] + 1);
+    // 32768 is the length of a TByteArray.
+    if FColumnsSize > 32767 then begin
+      raise Exception.Create('Zeos: Row buffer width exceeded.\nTry using fewer or longer columns in SQL query.');
+    end;
     FHasBlobs := FHasBlobs
       or (FColumnTypes[I] in [stAsciiStream, stUnicodeStream, stBinaryStream]);
   end;