wl-1884 storing NULL in ordered index

ndb/include/ndbapi/NdbIndexScanOperation.hpp

@@ -86,26 +86,25 @@ public:
   /**
    * Define bound on index key in range scan.
    *
-   * Each index key can have not null lower and/or upper bound, or can
-   * be set equal to not null value.  The bounds can be defined in any
-   * order but a duplicate definition is an error.
+   * Each index key can have lower and/or upper bound, or can be set
+   * equal to a value.  The bounds can be defined in any order but
+   * a duplicate definition is an error.
    *
-   * The scan is most effective when bounds are given for an initial
-   * sequence of non-nullable index keys, and all but the last one is an
-   * equality.  In this case the scan returns a contiguous range from
-   * each ordered index fragment.
+   * The bounds must specify a single range i.e. they are on an initial
+   * sequence of index keys and the condition is equality for all but
+   * (at most) the last key which has a lower and/or upper bound.
    *
-   * @note      This release implements only the case described above,
-   *            except for the non-nullable limitation.  Other sets of
-   *            bounds return error or empty result set.
+   * NULL is treated like a normal value which is less than any not-NULL
+   * value and equal to another NULL value.  To search for NULL use
+   * setBound with null pointer (0).
    *
-   * @note      In this release a null key value satisfies any lower
-   *            bound and no upper bound.  This may change.
+   * An index stores also all-NULL keys (this may become optional).
+   * Doing index scan with empty bound set returns all table tuples.
    *
    * @param attrName    Attribute name, alternatively:
-   * @param anAttrId    Index column id (starting from 0).
+   * @param anAttrId    Index column id (starting from 0)
    * @param type        Type of bound
-   * @param value       Pointer to bound value
+   * @param value       Pointer to bound value, 0 for NULL
    * @param len         Value length in bytes.
    *                    Fixed per datatype and can be omitted
    * @return            0 if successful otherwise -1

ndb/src/kernel/blocks/dbtux/Dbtux.hpp

@@ -446,6 +446,7 @@ private:
     Uint32 m_descPage;          // descriptor page
     Uint16 m_descOff;           // offset within the page
     Uint16 m_numAttrs;
+    bool m_storeNullKey;
     union {
     Uint32 nextPool;
     };
@@ -469,6 +470,7 @@ private:
     Uint32 m_descPage;          // copy from index level
     Uint16 m_descOff;
     Uint16 m_numAttrs;
+    bool m_storeNullKey;
     TreeHead m_tree;
     TupLoc m_freeLoc;           // one node pre-allocated for insert
     DLList<ScanOp> m_scanList;  // current scans on this fragment
@@ -993,7 +995,8 @@ Dbtux::Index::Index() :
   m_numFrags(0),
   m_descPage(RNIL),
   m_descOff(0),
-  m_numAttrs(0)
+  m_numAttrs(0),
+  m_storeNullKey(false)
 {
   for (unsigned i = 0; i < MaxIndexFragments; i++) {
     m_fragId[i] = ZNIL;
@@ -1012,6 +1015,7 @@ Dbtux::Frag::Frag(ArrayPool<ScanOp>& scanOpPool) :
   m_descPage(RNIL),
   m_descOff(0),
   m_numAttrs(ZNIL),
+  m_storeNullKey(false),
   m_tree(),
   m_freeLoc(),
   m_scanList(scanOpPool),

ndb/src/kernel/blocks/dbtux/DbtuxCmp.cpp

@@ -62,15 +62,15 @@ Dbtux::cmpSearchKey(const Frag& frag, unsigned& start, TableData searchKey, Cons
         }
       } else {
         jam();
-        // not NULL < NULL
-        ret = -1;
+        // not NULL > NULL
+        ret = +1;
         break;
       }
     } else {
       if (! entryData.ah().isNULL()) {
         jam();
-        // NULL > not NULL
-        ret = +1;
+        // NULL < not NULL
+        ret = -1;
         break;
       }
     }
@@ -116,15 +116,15 @@ Dbtux::cmpSearchKey(const Frag& frag, unsigned& start, TableData searchKey, Tabl
         }
       } else {
         jam();
-        // not NULL < NULL
-        ret = -1;
+        // not NULL > NULL
+        ret = +1;
         break;
       }
     } else {
       if (*entryKey != 0) {
         jam();
-        // NULL > not NULL
-        ret = +1;
+        // NULL < not NULL
+        ret = -1;
         break;
       }
     }
@@ -180,7 +180,7 @@ Dbtux::cmpScanBound(const Frag& frag, unsigned dir, ConstData boundInfo, unsigne
     // get and skip bound type
     type = boundInfo[0];
     boundInfo += 1;
-    ndbrequire(! boundInfo.ah().isNULL());
+    if (! boundInfo.ah().isNULL()) {
       if (! entryData.ah().isNULL()) {
         jam();
         // current attribute
@@ -205,12 +205,17 @@ Dbtux::cmpScanBound(const Frag& frag, unsigned dir, ConstData boundInfo, unsigne
         }
       } else {
         jam();
-      /*
-       * NULL is bigger than any bound, thus the boundary is always to
-       * the left of NULL.
-       */
+        // not NULL > NULL
+        return +1;
+      }
+    } else {
+      jam();
+      if (! entryData.ah().isNULL()) {
+        jam();
+        // NULL < not NULL
         return -1;
       }
+    }
     boundInfo += AttributeHeaderSize + boundInfo.ah().getDataSize();
     entryData += AttributeHeaderSize + entryData.ah().getDataSize();
     boundCount -= 1;
@@ -258,7 +263,7 @@ Dbtux::cmpScanBound(const Frag& frag, unsigned dir, ConstData boundInfo, unsigne
     // get and skip bound type
     type = boundInfo[0];
     boundInfo += 1;
-    ndbrequire(! boundInfo.ah().isNULL());
+    if (! boundInfo.ah().isNULL()) {
       if (*entryKey != 0) {
         jam();
         // current attribute
@@ -279,12 +284,17 @@ Dbtux::cmpScanBound(const Frag& frag, unsigned dir, ConstData boundInfo, unsigne
         }
       } else {
         jam();
-      /*
-       * NULL is bigger than any bound, thus the boundary is always to
-       * the left of NULL.
-       */
+        // not NULL > NULL
+        return +1;
+      }
+    } else {
+      jam();
+      if (*entryKey != 0) {
+        jam();
+        // NULL < not NULL
         return -1;
       }
+    }
     boundInfo += AttributeHeaderSize + boundInfo.ah().getDataSize();
     entryKey += 1;
     boundCount -= 1;

ndb/src/kernel/blocks/dbtux/DbtuxMaint.cpp

@@ -82,8 +82,8 @@ Dbtux::execTUX_MAINT_REQ(Signal* signal)
   ent.m_fragBit = fragBit;
   // read search key
   readKeyAttrs(frag, ent, 0, c_searchKey);
+  if (! frag.m_storeNullKey) {
     // check if all keys are null
-  {
     const unsigned numAttrs = frag.m_numAttrs;
     bool allNull = true;
     for (unsigned i = 0; i < numAttrs; i++) {

ndb/src/kernel/blocks/dbtux/DbtuxMeta.cpp

@@ -85,6 +85,7 @@ Dbtux::execTUXFRAGREQ(Signal* signal)
     fragPtr.p->m_fragOff = req->fragOff;
     fragPtr.p->m_fragId = req->fragId;
     fragPtr.p->m_numAttrs = req->noOfAttr;
+    fragPtr.p->m_storeNullKey = true;  // not yet configurable
     fragPtr.p->m_tupIndexFragPtrI = req->tupIndexFragPtrI;
     fragPtr.p->m_tupTableFragPtrI[0] = req->tupTableFragPtrI[0];
     fragPtr.p->m_tupTableFragPtrI[1] = req->tupTableFragPtrI[1];
@@ -111,6 +112,7 @@ Dbtux::execTUXFRAGREQ(Signal* signal)
       indexPtr.p->m_tableId = req->primaryTableId;
       indexPtr.p->m_fragOff = req->fragOff;
       indexPtr.p->m_numAttrs = req->noOfAttr;
+      indexPtr.p->m_storeNullKey = true;  // not yet configurable
       // allocate attribute descriptors
       if (! allocDescEnt(indexPtr)) {
         jam();

ndb/src/kernel/blocks/dbtux/DbtuxScan.cpp

@@ -137,7 +137,7 @@ Dbtux::execTUX_BOUND_INFO(Signal* signal)
   const Uint32* const data = (Uint32*)sig + TuxBoundInfo::SignalLength;
   unsigned offset = 5;
   // walk through entries
-  while (offset + 2 < req->boundAiLength) {
+  while (offset + 2 <= req->boundAiLength) {
     jam();
     const unsigned type = data[offset];
     if (type > 4) {

ndb/src/kernel/blocks/dbtux/Times.txt

@@ -21,11 +21,11 @@ shows ms / 1000 rows for each and pct overhead
 
 c
 1 million rows, index on PK, full table scan, full index scan
-shows ms / 1000 rows for each and index time pct
+shows ms / 1000 rows for each and index time overhead
 
 d
 1 million rows, index on PK, read table via each pk, scan index for each pk
-shows ms / 1000 rows for each and index time pct
+shows ms / 1000 rows for each and index time overhead
 samples 10% of all PKs (100,000 pk reads, 100,000 scans)
 
 040616          mc02/a  40 ms   87 ms   114 pct
@@ -66,12 +66,20 @@ optim 11        mc02/a  43 ms   63 ms    46 pct
 
 optim 12        mc02/a  38 ms   55 ms    43 pct
                 mc02/b  47 ms   77 ms    63 pct
-                mc02/c  10 ms   14 ms   147 pct
-                mc02/d 176 ms  281 ms   159 pct
+                mc02/c  10 ms   14 ms    47 pct
+                mc02/d 176 ms  281 ms    59 pct
 
 optim 13        mc02/a  40 ms   57 ms    42 pct
                 mc02/b  47 ms   77 ms    61 pct
-                mc02/c   9 ms   13 ms   150 pct
-                mc02/d 170 ms  256 ms   150 pct
+                mc02/c   9 ms   13 ms    50 pct
+                mc02/d 170 ms  256 ms    50 pct
+
+after wl-1884 store all-NULL keys (the tests have pctnull=10 per column)
+[ what happened to PK read performance? ]
+
+optim 13        mc02/a  39 ms   59 ms    50 pct
+                mc02/b  47 ms   77 ms    61 pct
+                mc02/c   9 ms   12 ms    44 pct
+                mc02/d 246 ms  289 ms    17 pct
 
 vim: set et:

ndb/src/ndbapi/NdbScanOperation.cpp

@@ -1125,7 +1125,6 @@ NdbIndexScanOperation::setBound(const NdbColumnImpl* tAttrInfo,
   if (theOperationType == OpenRangeScanRequest &&
       theStatus == SetBound &&
       (0 <= type && type <= 4) &&
-      aValue != NULL &&
       len <= 8000) {
     // bound type
 
@@ -1136,11 +1135,12 @@ NdbIndexScanOperation::setBound(const NdbColumnImpl* tAttrInfo,
       setErrorCodeAbort(4209);
       return -1;
     }
-    len = sizeInBytes;
+    len = aValue != NULL ? sizeInBytes : 0;
     Uint32 tIndexAttrId = tAttrInfo->m_attrId;
     Uint32 sizeInWords = (len + 3) / 4;
     AttributeHeader ah(tIndexAttrId, sizeInWords);
     insertATTRINFO(ah.m_value);
+    if (len != 0) {
       // attribute data
       if ((UintPtr(aValue) & 0x3) == 0 && (len & 0x3) == 0)
         insertATTRINFOloop((const Uint32*)aValue, sizeInWords);
@@ -1151,6 +1151,7 @@ NdbIndexScanOperation::setBound(const NdbColumnImpl* tAttrInfo,
           ((char*)temp)[len++] = 0;
         insertATTRINFOloop(temp, sizeInWords);
       }
+    }
 
     /**
      * Do sorted stuff
@@ -1236,7 +1237,7 @@ NdbIndexScanOperation::compare(Uint32 skip, Uint32 cols,
     Uint32 * d2 = (Uint32*)r2->aRef();
     unsigned r1_null = r1->isNULL();
     if((r1_null ^ (unsigned)r2->isNULL())){
-      return (r1_null ? 1 : -1);
+      return (r1_null ? -1 : 1);
     }
     Uint32 type = NdbColumnImpl::getImpl(* r1->m_column).m_extType;
     Uint32 size = (r1->theAttrSize * r1->theArraySize + 3) / 4;

ndb/test/ndbapi/testOIBasic.cpp

@@ -85,7 +85,7 @@ printhelp()
     << "  -dups         allow duplicate tuples from index scan [" << d.m_dups << "]" << endl
     << "  -fragtype T   fragment type single/small/medium/large" << endl
     << "  -index xyz    only given index numbers (digits 1-9)" << endl
-    << "  -loop N       loop count full suite forever=0 [" << d.m_loop << "]" << endl
+    << "  -loop N       loop count full suite 0=forever [" << d.m_loop << "]" << endl
     << "  -nologging    create tables in no-logging mode" << endl
     << "  -rows N       rows per thread [" << d.m_rows << "]" << endl
     << "  -samples N    samples for some timings (0=all) [" << d.m_samples << "]" << endl
@@ -102,6 +102,12 @@ printhelp()
   printtables();
 }
 
+// not yet configurable
+static const bool g_store_null_key = true;
+
+// compare NULL like normal value (NULL < not NULL, NULL == NULL)
+static const bool g_compare_null = true;
+
 // log and error macros
 
 static NdbMutex ndbout_mutex = NDB_MUTEX_INITIALIZER;
@@ -306,8 +312,8 @@ Tmr::pct(const Tmr& t1)
 const char*
 Tmr::over(const Tmr& t1)
 {
-  if (0 < t1.m_ms && t1.m_ms < m_ms) {
-    sprintf(m_text, "%u pct", (100 * (m_ms - t1.m_ms)) / t1.m_ms);
+  if (0 < t1.m_ms) {
+    sprintf(m_text, "%d pct", (100 * (m_ms - t1.m_ms)) / t1.m_ms);
   } else {
     sprintf(m_text, "[cannot measure]");
   }
@@ -1168,9 +1174,9 @@ Val::cmp(const Val& val2) const
   assert(col.m_type == col2.m_type && col.m_length == col2.m_length);
   if (m_null || val2.m_null) {
     if (! m_null)
-      return -1;
-    if (! val2.m_null)
       return +1;
+    if (! val2.m_null)
+      return -1;
     return 0;
   }
   // verify data formats
@@ -1695,8 +1701,8 @@ int
 BVal::setbnd(Par par) const
 {
   Con& con = par.con();
-  const char* addr = (const char*)dataaddr();
-  assert(! m_null);
+  assert(g_compare_null || ! m_null);
+  const char* addr = ! m_null ? (const char*)dataaddr() : 0;
   const ICol& icol = m_icol;
   CHK(con.setBound(icol.m_num, m_type, addr) == 0);
   return 0;
@@ -1785,6 +1791,7 @@ BSet::calc(Par par)
       if (k + 1 < itab.m_icols)
         bval.m_type = 4;
       // value generation parammeters
+      if (! g_compare_null)
         par.m_pctnull = 0;
       par.m_pctrange = 50;      // bit higher
       do {
@@ -1842,6 +1849,7 @@ BSet::filter(const Set& set, Set& set2) const
     if (! set.exist(i))
       continue;
     const Row& row = *set.m_row[i];
+    if (! g_store_null_key) {
       bool ok1 = false;
       for (unsigned k = 0; k < itab.m_icols; k++) {
         const ICol& icol = itab.m_icol[k];
@@ -1854,6 +1862,7 @@ BSet::filter(const Set& set, Set& set2) const
       }
       if (! ok1)
         continue;
+    }
     bool ok2 = true;
     for (unsigned j = 0; j < m_bvals; j++) {
       const BVal& bval = *m_bval[j];
@@ -2727,13 +2736,13 @@ tpkops(Par par)
   RUNSTEP(par, pkinsert, MT);
   RUNSTEP(par, createindex, ST);
   RUNSTEP(par, invalidateindex, MT);
-  RUNSTEP(par, readverify, MT);
+  RUNSTEP(par, readverify, ST);
   for (unsigned i = 0; i < par.m_subloop; i++) {
     RUNSTEP(par, pkupdatescanread, MT);
-    RUNSTEP(par, readverify, MT);
+    RUNSTEP(par, readverify, ST);
   }
   RUNSTEP(par, pkdelete, MT);
-  RUNSTEP(par, readverify, MT);
+  RUNSTEP(par, readverify, ST);
   return 0;
 }
 
@@ -2746,10 +2755,10 @@ tmixedops(Par par)
   RUNSTEP(par, pkinsert, MT);
   RUNSTEP(par, createindex, ST);
   RUNSTEP(par, invalidateindex, MT);
-  RUNSTEP(par, readverify, MT);
+  RUNSTEP(par, readverify, ST);
   for (unsigned i = 0; i < par.m_subloop; i++) {
     RUNSTEP(par, mixedoperations, MT);
-    RUNSTEP(par, readverify, MT);
+    RUNSTEP(par, readverify, ST);
   }
   return 0;
 }
@@ -2832,7 +2841,7 @@ ttimescan(Par par)
   }
   LL1("full scan table - " << t1.time());
   LL1("full scan PK index - " << t2.time());
-  LL1("index time pct - " << t2.pct(t1));
+  LL1("overhead - " << t2.over(t1));
   return 0;
 }
 
@@ -2854,7 +2863,7 @@ ttimepkread(Par par)
   }
   LL1("pk read table - " << t1.time());
   LL1("pk read PK index - " << t2.time());
-  LL1("index time pct - " << t2.pct(t1));
+  LL1("overhead - " << t2.over(t1));
   return 0;
 }