ndb Updated example

ndb/examples/ndbapi_scan_example/ndbapi_scan.cpp:
  Updated example
ndb/include/ndbapi/NdbScanFilter.hpp:
  Fix default value

ndb/examples/ndbapi_scan_example/ndbapi_scan.cpp

@@ -30,15 +30,19 @@
  *       getDictionary()
  *       startTransaction()
  *       closeTransaction()
- *       sendPreparedTransactions()
- *       pollNdb()
  *
- *  NdbConnection
- *       getNdbOperation()
- *       executeAsynchPrepare()
- *       getNdbError()
- *       executeScan()
- *       nextScanResult()
+ *  NdbTransaction
+ *       getNdbScanOperation()
+ *       execute()
+ *
+ *  NdbResultSet
+ *
+ *  NdbScanOperation
+ *       getValue() 
+ *       readTuples()
+ *       nextResult()
+ *       deleteCurrentTuple()
+ *       updateCurrentTuple()
  *
  *  NdbDictionary::Dictionary
  *       getTable()
@@ -60,33 +64,15 @@
  *       insertTuple()
  *       equal()
  *       setValue()
- *       openScanRead()
- *       openScanExclusive()
- *
- *  NdbRecAttr
- *       aRef()
- *       u_32_value()
- *
- *  NdbResultSet
- *       nextResult()
- *       deleteTuple()
- *       updateTuple()
- *
- *  NdbScanOperation
- *       getValue() 
- *       readTuplesExclusive()
  *
  *  NdbScanFilter
  *       begin()
  *	 eq()
  *	 end()
  *
- *       
  */
 
 
-#include <ndb_global.h>
-
 #include <NdbApi.hpp>
 #include <NdbScanFilter.hpp>
 // Used for cout
@@ -114,30 +100,12 @@ milliSleep(int milliseconds){
               << error.code << ", msg: " << error.message << "." << std::endl; \
     exit(-1); }
 
-/*
- *   callback : This is called when the transaction is polled
- *              
- *   (This function must have three arguments: 
- *   - The result of the transaction, 
- *   - The NdbConnection object, and 
- *   - A pointer to an arbitrary object.)
- */
-static void
-callback(int result, NdbConnection* myTrans, void* aObject)
+struct Car 
 {
-  if (result == -1) {
-    std::cout << "In callback: " << std::endl;     
-    /**
-     * Put error checking code here (see ndb_async_example)
-     */
-    APIERROR(myTrans->getNdbError());
-  } else {
-    /**
-     * Ok!
-     */
-    return;
-  }
-}
+  unsigned int reg_no;
+  char brand[20];
+  char color[20];
+};
 
 /**
  * Function to create table
@@ -162,6 +130,8 @@ int create_table(Ndb * myNdb)
     }
   } 
   
+  Car car;
+
   myTable.setName("GARAGE");
   
   myColumn.setName("REG_NO");
@@ -173,7 +143,7 @@ int create_table(Ndb * myNdb)
 
   myColumn.setName("BRAND");
   myColumn.setType(NdbDictionary::Column::Char);
-  myColumn.setLength(20);
+  myColumn.setLength(sizeof(car.brand));
   myColumn.setPrimaryKey(false);
   myColumn.setNullable(false);
   myTable.addColumn(myColumn);
@@ -181,7 +151,7 @@ int create_table(Ndb * myNdb)
 
   myColumn.setName("COLOR");
   myColumn.setType(NdbDictionary::Column::Char);
-  myColumn.setLength(20);
+  myColumn.setLength(sizeof(car.color));
   myColumn.setPrimaryKey(false);
   myColumn.setNullable(false);
   myTable.addColumn(myColumn);
@@ -196,91 +166,64 @@ int create_table(Ndb * myNdb)
 
 int populate(Ndb * myNdb)
 {
-  NdbConnection*  myNdbConnection[15];   // For transactions
-  NdbOperation*   myNdbOperation;       // For operations
-  /******************************************************
-   * Insert (we do 15 insert transactions in parallel) *
-   ******************************************************/
+  int i;
+  Car cars[15];
+
   /**
    * Five blue mercedes
    */
-  for (int i = 0; i < 5; i++) 
+  for (i = 0; i < 5; i++)
   {
-    myNdbConnection[i] = myNdb->startTransaction();
-    if (myNdbConnection[i] == NULL) 
-      APIERROR(myNdb->getNdbError());
-    myNdbOperation = myNdbConnection[i]->getNdbOperation("GARAGE");
-    // Error check. If error, then maybe table GARAGE is not in database
-    if (myNdbOperation == NULL) 
-      APIERROR(myNdbConnection[i]->getNdbError());
-    myNdbOperation->insertTuple();
-    myNdbOperation->equal("REG_NO", i);
-    myNdbOperation->setValue("BRAND", "Mercedes");
-    myNdbOperation->setValue("COLOR", "Blue");
-    // Prepare transaction (the transaction is NOT yet sent to NDB)
-    myNdbConnection[i]->executeAsynchPrepare(Commit, &callback, NULL);
+    cars[i].reg_no = i;
+    sprintf(cars[i].brand, "Mercedes");
+    sprintf(cars[i].color, "Blue");
   }
 
-
   /**
    * Five black bmw
    */
-  for (int i = 5; i < 10; i++) 
+  for (i = 5; i < 10; i++)
   {
-    myNdbConnection[i] = myNdb->startTransaction();
-    if (myNdbConnection[i] == NULL)
-      APIERROR(myNdb->getNdbError());
-    myNdbOperation = myNdbConnection[i]->getNdbOperation("GARAGE");
-    // Error check. If error, then maybe table MYTABLENAME is not in database
-    if (myNdbOperation == NULL) 
-      APIERROR(myNdbConnection[i]->getNdbError());
-    myNdbOperation->insertTuple();
-    myNdbOperation->equal("REG_NO", i);
-    myNdbOperation->setValue("BRAND", "BMW");
-    myNdbOperation->setValue("COLOR", "Black");
-    // Prepare transaction (the transaction is NOT yet sent to NDB)
-    myNdbConnection[i]->executeAsynchPrepare(Commit, &callback, NULL);
+    cars[i].reg_no = i;
+    sprintf(cars[i].brand, "BMW");
+    sprintf(cars[i].color, "Black");
   }
 
   /**
    * Five pink toyotas
    */
-  for (int i = 10; i < 15; i++) {
-    myNdbConnection[i] = myNdb->startTransaction();
-    if (myNdbConnection[i] == NULL) APIERROR(myNdb->getNdbError());
-    myNdbOperation = myNdbConnection[i]->getNdbOperation("GARAGE");
+  for (i = 10; i < 15; i++)
+  {
+    cars[i].reg_no = i;
+    sprintf(cars[i].brand, "Toyota");
+    sprintf(cars[i].color, "Pink");
+  }
+  
+  NdbTransaction* myTrans = myNdb->startTransaction();
+  if (myTrans == NULL)
+    APIERROR(myNdb->getNdbError());
+
+  for (i = 0; i < 15; i++) 
+  {
+    NdbOperation* myNdbOperation = myTrans->getNdbOperation("GARAGE");
     // Error check. If error, then maybe table MYTABLENAME is not in database
-    if (myNdbOperation == NULL) APIERROR(myNdbConnection[i]->getNdbError());
+    if (myNdbOperation == NULL) 
+      APIERROR(myTrans->getNdbError());
     myNdbOperation->insertTuple();
-    myNdbOperation->equal("REG_NO", i);
-    myNdbOperation->setValue("BRAND", "Toyota");
-    myNdbOperation->setValue("COLOR", "Pink");
-    // Prepare transaction (the transaction is NOT yet sent to NDB)
-    myNdbConnection[i]->executeAsynchPrepare(Commit, &callback, NULL);
-  }
-
-  // Send all transactions to NDB 
-  myNdb->sendPreparedTransactions(0);
-  // Poll all transactions
-  myNdb->pollNdb(3000, 0);
-
-  //  it is also possible to use sendPollNdb instead of
-  //  myNdb->sendPreparedTransactions(0); and myNdb->pollNdb(3000, 15);  above.
-  //  myNdb->sendPollNdb(3000,0);
-  //  Note! Neither sendPollNdb or pollNdb returs until all 15 callbacks have 
-  //  executed.
-
-  //  Close all transactions. It is also possible to close transactions
-  //  in the callback.
-  for (int i = 0; i < 15; i++) 
-    myNdb->closeTransaction(myNdbConnection[i]);
-  return 1;
+    myNdbOperation->equal("REG_NO", cars[i].reg_no);
+    myNdbOperation->setValue("BRAND", cars[i].brand);
+    myNdbOperation->setValue("COLOR", cars[i].color);
+  }
+
+  int check = myTrans->execute(Commit);
+
+  myTrans->close();
+
+  return check != -1;
 }
 
 int scan_delete(Ndb* myNdb, 
-		int parallelism,
 		int column,
-		int column_len,
 		const char * color)
   
 {
@@ -342,8 +285,8 @@ int scan_delete(Ndb* myNdb,
     /**
      * Define a result set for the scan.
      */ 
-    NdbResultSet * rs = myScanOp->readTuplesExclusive(parallelism);
-    if( rs == 0 ) {
+    if(myScanOp->readTuples(NdbOperation::LM_Exclusive) != 0)
+    {
       std::cout << myTrans->getNdbError().message << std::endl;
       myNdb->closeTransaction(myTrans);
       return -1;
@@ -354,8 +297,8 @@ int scan_delete(Ndb* myNdb,
      */ 
     NdbScanFilter filter(myScanOp) ;   
     if(filter.begin(NdbScanFilter::AND) < 0  || 
-       filter.eq(column, color, column_len, false) <0||
-       filter.end() <0)
+       filter.cmp(NdbScanFilter::COND_EQ, column, color) < 0 ||
+       filter.end() < 0)
     {
       std::cout <<  myTrans->getNdbError().message << std::endl;
       myNdb->closeTransaction(myTrans);
@@ -384,9 +327,11 @@ int scan_delete(Ndb* myNdb,
     * start of loop: nextResult(true) means that "parallelism" number of
     * rows are fetched from NDB and cached in NDBAPI
     */    
-    while((check = rs->nextResult(true)) == 0){
-      do {
-	if (rs->deleteTuple() != 0){
+    while((check = myScanOp->nextResult(true)) == 0){
+      do 
+      {
+	if (myScanOp->deleteCurrentTuple() != 0)
+	{
 	  std::cout << myTrans->getNdbError().message << std::endl;
 	  myNdb->closeTransaction(myTrans);
 	  return -1;
@@ -398,21 +343,32 @@ int scan_delete(Ndb* myNdb,
 	 * cached in the NDBAPI are modified before
 	 * fetching more rows from NDB.
 	 */    
-      } while((check = rs->nextResult(false)) == 0);
+      } while((check = myScanOp->nextResult(false)) == 0);
       
       /**
        * Commit when all cached tuple have been marked for deletion
        */    
-      if(check != -1){
+      if(check != -1)
+      {
 	check = myTrans->execute(Commit);   
-	myTrans->releaseCompletedOperations();
       }
+
+      if(check == -1)
+      {
+	/**
+	 * Create a new transaction, while keeping scan open
+	 */
+	check = myTrans->restart();
+      }
+
       /**
        * Check for errors
        */
       err = myTrans->getNdbError();    
-      if(check == -1){
-	if(err.status == NdbError::TemporaryError){
+      if(check == -1)
+      {
+	if(err.status == NdbError::TemporaryError)
+	{
 	  std::cout << myTrans->getNdbError().message << std::endl;
 	  myNdb->closeTransaction(myTrans);
 	  milliSleep(50);
@@ -426,10 +382,10 @@ int scan_delete(Ndb* myNdb,
     std::cout << myTrans->getNdbError().message << std::endl;
     myNdb->closeTransaction(myTrans);
     return 0;
-
-    
   }
-  if(myTrans!=0) {
+  
+  if(myTrans!=0) 
+  {
     std::cout << myTrans->getNdbError().message << std::endl;
     myNdb->closeTransaction(myTrans);
   }
@@ -438,10 +394,7 @@ int scan_delete(Ndb* myNdb,
 
 
 int scan_update(Ndb* myNdb, 
-		int parallelism,
-		int column_len,
 		int update_column,
-		const char * column_name,
 		const char * before_color,
 		const char * after_color)
 		
@@ -505,8 +458,8 @@ int scan_update(Ndb* myNdb,
     /**
      * Define a result set for the scan.
      */ 
-    NdbResultSet * rs = myScanOp->readTuplesExclusive(parallelism);
-    if( rs == 0 ) {
+    if( myScanOp->readTuplesExclusive(NdbOperation::LM_Exclusive) ) 
+    {
       std::cout << myTrans->getNdbError().message << std::endl;
       myNdb->closeTransaction(myTrans);
       return -1;
@@ -517,7 +470,7 @@ int scan_update(Ndb* myNdb,
      */ 
     NdbScanFilter filter(myScanOp) ;   
     if(filter.begin(NdbScanFilter::AND) < 0  || 
-       filter.eq(update_column, before_color, column_len, false) <0||
+       filter.cmp(NdbScanFilter::COND_EQ, update_column, before_color) <0||
        filter.end() <0)
     {
       std::cout <<  myTrans->getNdbError().message << std::endl;
@@ -528,7 +481,8 @@ int scan_update(Ndb* myNdb,
     /**
      * Start scan    (NoCommit since we are only reading at this stage);
      */     
-    if(myTrans->execute(NoCommit) != 0){      
+    if(myTrans->execute(NoCommit) != 0)
+    {      
       err = myTrans->getNdbError();    
       if(err.status == NdbError::TemporaryError){
 	std::cout << myTrans->getNdbError().message << std::endl;
@@ -541,49 +495,49 @@ int scan_update(Ndb* myNdb,
       return -1;
     }
 
-   /**
-    * Define an update operation
-    */    
-    NdbOperation * myUpdateOp;
     /**
      * start of loop: nextResult(true) means that "parallelism" number of
      * rows are fetched from NDB and cached in NDBAPI
      */    
-    while((check = rs->nextResult(true)) == 0){
+    while((check = myScanOp->nextResult(true)) == 0){
       do {
 	/**
 	 * Get update operation
 	 */    
-	myUpdateOp = rs->updateTuple();
-	if (myUpdateOp == 0){
+	NdbOperation * myUpdateOp = myScanOp->updateCurrentTuple();
+	if (myUpdateOp == 0)
+	{
 	  std::cout << myTrans->getNdbError().message << std::endl;
 	  myNdb->closeTransaction(myTrans);
 	  return -1;
 	}
 	updatedRows++;
+
 	/**
 	 * do the update
 	 */    
-	myUpdateOp->setValue(update_column,after_color);
+	myUpdateOp->setValue(update_column, after_color);
 	/**
 	 * nextResult(false) means that the records 
 	 * cached in the NDBAPI are modified before
 	 * fetching more rows from NDB.
 	 */    
-      } while((check = rs->nextResult(false)) == 0);
+      } while((check = myScanOp->nextResult(false)) == 0);
       
       /**
-       * Commit when all cached tuple have been updated
+       * NoCommit when all cached tuple have been updated
        */    
-      if(check != -1){
-	check = myTrans->execute(Commit);   
-	myTrans->releaseCompletedOperations();
+      if(check != -1)
+      {
+	check = myTrans->execute(NoCommit);   
       }
+
       /**
        * Check for errors
        */
       err = myTrans->getNdbError();    
-      if(check == -1){
+      if(check == -1)
+      {
 	if(err.status == NdbError::TemporaryError){
 	  std::cout << myTrans->getNdbError().message << std::endl;
 	  myNdb->closeTransaction(myTrans);
@@ -595,13 +549,28 @@ int scan_update(Ndb* myNdb,
        * End of loop 
        */
     }
+
+    /**
+     * Commit all prepared operations
+     */
+    if(myTrans->execute(Commit) == -1)
+    {
+      if(err.status == NdbError::TemporaryError){
+	std::cout << myTrans->getNdbError().message << std::endl;
+	myNdb->closeTransaction(myTrans);
+	milliSleep(50);
+	continue;
+      }	
+    }
+
     std::cout << myTrans->getNdbError().message << std::endl;
     myNdb->closeTransaction(myTrans);
     return 0;    
+  }
 
 
-  }
-  if(myTrans!=0) {
+  if(myTrans!=0) 
+  {
     std::cout << myTrans->getNdbError().message << std::endl;
     myNdb->closeTransaction(myTrans);
   }
@@ -610,9 +579,7 @@ int scan_update(Ndb* myNdb,
 
 
 
-int scan_print(Ndb * myNdb, int parallelism, 
-	       int column_len_brand, 
-	       int column_len_color) 
+int scan_print(Ndb * myNdb)
 {
 // Scan all records exclusive and update
   // them one by one
@@ -674,10 +641,10 @@ int scan_print(Ndb * myNdb, int parallelism,
     }
 
     /**
-     * Define a result set for the scan.
+     * Read without locks, without being placed in lock queue
      */
-    NdbResultSet * rs = myScanOp->readTuplesExclusive(parallelism);
-    if( rs == 0 ) {
+    if( myScanOp->readTuples(NdbOperation::LM_CommittedRead) == -1)
+    {
       std::cout << myTrans->getNdbError().message << std::endl;
       myNdb->closeTransaction(myTrans);
       return -1;
@@ -719,7 +686,7 @@ int scan_print(Ndb * myNdb, int parallelism,
      * start of loop: nextResult(true) means that "parallelism" number of
      * rows are fetched from NDB and cached in NDBAPI
      */    
-    while((check = rs->nextResult(true)) == 0){
+    while((check = myScanOp->nextResult(true)) == 0){
       do {
 	
 	fetchedRows++;
@@ -727,28 +694,23 @@ int scan_print(Ndb * myNdb, int parallelism,
 	 * print  REG_NO unsigned int
 	 */
 	std::cout << myRecAttr[0]->u_32_value() << "\t";
-	char * buf_brand = new char[column_len_brand+1];
-	char * buf_color = new char[column_len_color+1];
+
 	/**
 	 * print  BRAND character string
 	 */
-	memcpy(buf_brand, myRecAttr[1]->aRef(), column_len_brand);
-	buf_brand[column_len_brand] = 0;
-	std::cout << buf_brand << "\t";
-	delete [] buf_brand;
+	std::cout << myRecAttr[1]->aRef() << "\t";
+
 	/**
 	 * print  COLOR character string
 	 */
-	memcpy(buf_color, myRecAttr[2]->aRef(), column_len_color);
-	buf_brand[column_len_color] = 0;
-	std::cout << buf_color << std::endl;
-	delete [] buf_color;	
+	std::cout << myRecAttr[2]->aRef() << std::endl;
+
 	/**
 	 * nextResult(false) means that the records 
 	 * cached in the NDBAPI are modified before
 	 * fetching more rows from NDB.
 	 */    
-      } while((check = rs->nextResult(false)) == 0);
+      } while((check = myScanOp->nextResult(false)) == 0);
 
     }    
     myNdb->closeTransaction(myTrans);
@@ -762,55 +724,67 @@ int scan_print(Ndb * myNdb, int parallelism,
 int main()
 {
   ndb_init();
-  Ndb* myNdb = new Ndb( "TEST_DB" );  // Object representing the database
 
+  Ndb_cluster_connection cluster_connection;
+
+  if (cluster_connection.connect(12, 5, 1))
+  {
+    std::cout << "Unable to connect to cluster within 30 secs." << std::endl;
+    exit(-1);
+  }
+
+  if (cluster_connection.wait_until_ready(30,30))
+  {
+    std::cout << "Cluster was not ready within 30 secs." << std::endl;
+    exit(-1);
+  }
   
+  Ndb myNdb(&cluster_connection,"TEST_DB" );  
   
   /*******************************************
    * Initialize NDB and wait until its ready *
    *******************************************/
-  if (myNdb->init(1024) == -1) {          // Set max 1024  parallel transactions
-    APIERROR(myNdb->getNdbError());
+  if (myNdb.init(1024) == -1) {          // Set max 1024  parallel transactions
+    APIERROR(myNdb.getNdbError());
     exit(-1);
   }
 
-  if (myNdb->waitUntilReady(30) != 0) {
-    std::cout << "NDB was not ready within 30 secs." << std::endl;
-    exit(-1);
-  }
-  create_table(myNdb);
+  create_table(&myNdb);
   
-  NdbDictionary::Dictionary* myDict = myNdb->getDictionary();
+  NdbDictionary::Dictionary* myDict = myNdb.getDictionary();
   int column_color = myDict->getTable("GARAGE")->getColumn("COLOR")->getColumnNo();
-  int column_len_color = 
-    myDict->getTable("GARAGE")->getColumn("COLOR")->getLength();
-  int column_len_brand = 
-    myDict->getTable("GARAGE")->getColumn("BRAND")->getLength();
-  int parallelism = 16;
   
-
-  if(populate(myNdb) > 0)
+  if(populate(&myNdb) > 0)
     std::cout << "populate: Success!" << std::endl;
   
-  if(scan_print(myNdb, parallelism, column_len_brand, column_len_color) > 0)
+  if(scan_print(&myNdb) > 0)
     std::cout << "scan_print: Success!" << std::endl  << std::endl;
   
   std::cout << "Going to delete all pink cars!" << std::endl;
-  if(scan_delete(myNdb, parallelism, column_color,
-		 column_len_color, "Pink") > 0)
+  
+  {
+    /**
+     * Note! color needs to be of exact the same size as column defined
+     */
+    char color[20] = "Pink";
+    if(scan_delete(&myNdb, column_color, color) > 0)
       std::cout << "scan_delete: Success!" << std::endl  << std::endl;
+  }
 
-  if(scan_print(myNdb, parallelism, column_len_brand, column_len_color) > 0)
+  if(scan_print(&myNdb) > 0)
     std::cout << "scan_print: Success!" << std::endl  << std::endl;
   
-  std::cout << "Going to update all blue cars to black cars!" << std::endl;
-  if(scan_update(myNdb, parallelism, column_len_color, column_color, 
-		 "COLOR", "Blue", "Black") > 0) 
   {
+    /**
+     * Note! color1 & 2 need to be of exact the same size as column defined
+     */
+    char color1[20] = "Blue";
+    char color2[20] = "Black";
+    std::cout << "Going to update all " << color1 
+	      << " cars to " << color2 << " cars!" << std::endl;
+    if(scan_update(&myNdb, column_color, color1, color2) > 0) 
       std::cout << "scan_update: Success!" << std::endl  << std::endl;
   }
-  if(scan_print(myNdb, parallelism, column_len_brand, column_len_color) > 0)
+  if(scan_print(&myNdb) > 0)
     std::cout << "scan_print: Success!" << std::endl  << std::endl;
-
-  delete myNdb; 
 }

ndb/include/ndbapi/NdbScanFilter.hpp

@@ -88,7 +88,7 @@ public:
   /**
    * Compare column <b>ColId</b> with <b>val</b>
    */
-  int cmp(BinaryCondition cond, int ColId, const void *val, Uint32 len); 
+  int cmp(BinaryCondition cond, int ColId, const void *val, Uint32 len = 0); 
 
   /** 
    * @name Integer Comparators