Index: trunk/ippTools/src/diffphottool.c
===================================================================
--- trunk/ippTools/src/diffphottool.c	(revision 28387)
+++ trunk/ippTools/src/diffphottool.c	(revision 28412)
@@ -38,4 +38,5 @@
 static bool advanceMode(pxConfig *config);
 static bool revertMode(pxConfig *config);
+static bool dataMode(pxConfig *config);
 
 # define MODECASE(caseName, func) \
@@ -64,4 +65,5 @@
         MODECASE(DIFFPHOTTOOL_MODE_ADVANCE,   advanceMode);
         MODECASE(DIFFPHOTTOOL_MODE_REVERT,    revertMode);
+        MODECASE(DIFFPHOTTOOL_MODE_DATA,      dataMode);
 
         default:
@@ -490,2 +492,61 @@
 }
 
+static bool dataMode(pxConfig *config)
+{
+    PS_ASSERT_PTR_NON_NULL(config, false);
+
+    psMetadata *where = psMetadataAlloc();
+
+    PXOPT_COPY_S64(config->args, where,  "-diff_phot_id", "diff_phot_id", "==");
+    PXOPT_COPY_STR(config->args, where, "-skycell_id", "skycell_id", "==");
+
+    PXOPT_LOOKUP_U64(limit, config->args, "-limit", false, false);
+    PXOPT_LOOKUP_BOOL(simple, config->args, "-simple", false);
+
+    psString query = pxDataGet("diffphottool_data.sql");
+    if (!query) {
+        psError(PXTOOLS_ERR_SYS, false, "failed to retreive SQL statement");
+        return false;
+    }
+
+    if (psListLength(where->list)) {
+        psString clause = psDBGenerateWhereConditionSQL(where, NULL);
+        psStringAppend(&query, "\nWHERE %s", clause);
+        psFree(clause);
+    }
+    psFree(where);
+
+    if (limit) {
+        psString limitString = psDBGenerateLimitSQL(limit);
+        psStringAppend(&query, "\n%s", limitString);
+        psFree(limitString);
+    }
+
+    if (!p_psDBRunQuery(config->dbh, query)) {
+        psError(psErrorCodeLast(), false, "database error");
+        psFree(query);
+        return false;
+    }
+    psFree(query);
+
+    psArray *output = p_psDBFetchResult(config->dbh);
+    if (!output) {
+        psError(psErrorCodeLast(), false, "database error");
+        return false;
+    }
+    if (!psArrayLength(output)) {
+        psTrace("diffphottool", PS_LOG_INFO, "no rows found");
+        psFree(output);
+        return true;
+    }
+
+    if (!ippdbPrintMetadatas(stdout, output, "diffPhotSkyfile", !simple)) {
+        psError(psErrorCodeLast(), false, "failed to print array");
+        psFree(output);
+        return false;
+    }
+    psFree(output);
+
+    return true;
+}
+