harnessing the power of relational database servers

... Product in the database Lines 31-33 change the values of the data members in this instance of Product (in the database) Line 35 commits the changes to the database, and line 36 closes the database ... arrays of structures in C++ The columns in the database table are like the data members of the structure The rows in the table are like the elements of the array It's important to note that database ... editing of the database Think carefully about the granularity of the data in the fields Make each field as granular or precise as possible The usefulness of the database depends on the integrity of...

Ngày tải lên: 13/08/2014, 08:20

... from the client application This is the essence of multitier database application development The idea is to take advantage of the power of the relational database servers to reduce the number of ... on Day 6, "Harnessing the Power of Relational Database Servers. " The SQL UPDATE Statement The SQL UPDATE statement enables you to modify the data in existing records in the database The basic ... delete the records in the Recordset The changes made to the Recordset are applied to the database In other words, if you change the records in the Recordset, you change records in the database The...

Ngày tải lên: 13/08/2014, 08:20

... when there is some kind of database failure? Relational database servers typically log all the changes to the data The database writes to the log file first and then commits the changes to the database ... object per record in the database The result was a marginal gain in the performance of the database However, because of its lack of conformance to the relational model, the database could not be ... understanding of relational database servers, COM, and Microsoftís database client APIs q Day You discover the powerful innovations of relational database servers q q q Day You acquire an understanding of...

Ngày tải lên: 13/08/2014, 08:20

... does the Win32 subsystem know which DLL contains the code for the classes? The answer is that the COM libraries (part of the Win32 subsystem) look in the registry for the name of the DLL and the ... and Day 6, "Harnessing the Power of Relational Database Servers. " An Overview of Database Client Technologies Database client technologies provide abstractions That is their purpose A database is ... developed These database interfaces differ from each other in the things they accomplish and the way they go about them The popular database interfaces on the Windows platforms include q ODBC (open database...

Ngày tải lên: 13/08/2014, 08:20

... in the database ADOMFC1.EXE has intimate knowledge of the database The code in ADOMFC1.EXE knows the names of the tables and their fields, and the relationships between the tables If the database ... and not fit the relational definition of an atomic data type In addition, the type system of a relational database is established by the database itself Data of the supported types are the all that ... nature of a C++ object database and the openness and availability of a relational database Figure 13.2 : The relative openness of object databases and relational databases Some applications lend themselves...

Ngày tải lên: 13/08/2014, 08:21

... Microsoft introduced the DAO API This API was developed as the API for the Microsoft Jet Database engine The Microsoft Jet Database Engine is the database engine for Microsoft Access The Jet Database ... number of times the application must access the database, the performance will be dramatically faster than if the application has to hit the database frequently To reduce the number of database ... specific database The connection definition contains information about the type of database, as well as the pertinent location information for the database It then assigns a common name, called the...

Ngày tải lên: 13/08/2014, 08:21

... offset length of the column for the value // in the buffer 122: rgBind[i].obValue = dwOffset + offsetof(COLUMNDATA,bData); 123: // Set the offset length of the column for the length // in the buffer ... rgBind[i].obLength = dwOffset + offsetof (COLUMNDATA,dwLength); 125: // Set the offset length of the column for the status // in the buffer 126: rgBind[i].obStatus = dwOffset + offsetof (COLUMNDATA,wStatus); ... Description The name of the data source The parse name of the data source, used by the ParseDisplayName method to create a moniker The data source description A flag describing the type of the source...

Ngày tải lên: 13/08/2014, 08:21

... from a table, the name of the field in the resulting row set is the same as the name of the field in the table You can change the name of the field in the resulting row set by using the technique ... in the row buffer The iOrdinal field defines the ordinal position of the field The obValue field defines the buffer offset (the number of bytes from the beginning of the row buffer) to where the ... stored The obLength field defines the buffer offset to where the length of the column is stored The obStatus field defines the buffer offset to where the status of the column is stored The pObject...

Ngày tải lên: 13/08/2014, 08:21

... the name of the help file, including the path The GetSource method returns the name of the source operating-system object that generated the error The source name is generally the name of the dynamic ... compendium of the SQL command language, I discussed the use of the GetProperties method of the IDBProperties interface to determine whether the data provider supported the SQL command language The property ... defines the number of key columns in the start range key The pStartKeyData parameter specifies the start key data The lNumEndKeyCols defines the number of key columns in the end range key The pEndKeyData...

Ngày tải lên: 13/08/2014, 08:21

... Exercises Day 6, "Harnessing the Power of Relational Database Servers" r r q Quiz Exercises Day 7, "Database Design" r r q Quiz Exercises Day 8, "Utilizing the Capabilities of Database Servers" r Quiz ... change one of the order numbers in the table by typing in letters for the contents of the field When you move the cursor off that record, what happens? Does the database validate the data type ... What databases help you preserve the referential integrity of your data? The databases that help you preserve the referential integrity of your data are relational database servers and Microsoft...

Ngày tải lên: 13/08/2014, 08:21

... press to get the object to what you need, and what the lights mean about the status of the object The details of how the box is put together inside are irrelevant while you are using the box What ... some action The order and timing of these messages is determined by the actions of the user, and not by the control flow of the program Object orientation is a natural for this kind of programming ... parts The top part is used to hold the name of the class The middle part shows attributes, and the bottom is used to hold the class operations (methods) Depending on the level of detail needed, the...

Ngày tải lên: 22/08/2013, 14:52

... press to get the object to what you need, and what the lights mean about the status of the object The details of how the box is put together inside are irrelevant while you are using the box What ... some action The order and timing of these messages is determined by the actions of the user, and not by the control flow of the program Object orientation is a natural for this kind of programming ... parts The top part is used to hold the name of the class The middle part shows attributes, and the bottom is used to hold the class operations (methods) Depending on the level of detail needed, the...

Ngày tải lên: 20/12/2013, 21:16

... another theater at the other end of town Of course, because we're good businessmen, the theater we purchased is modern and already has some software to manage the screens Unfortunately, the software ... But of course we want to manage both theaters with the same application Let's just assume that using the new theater's software is out of the question But our new theater has features our software ... even break the whole class to access these methods or change the value of these properties Interfaces The sum of the properties and methods that are visible to the outside world is called the object's...

Ngày tải lên: 21/12/2013, 20:15

... Using Object References If you code the AS clause, the Compiler uses the value of the literal as the external name of the class program; otherwise it uses the class name changed to upper case ... describes the behavior of two different objects: • The factory object • The instances of the class There is never more than one occurrence of each type of factory object in an application, whereas there ... overrides the method in the class; the method in the subclass is known as a reimplementation of the method in the class For example, our banking application might handle the following types of account:...

Ngày tải lên: 12/02/2014, 23:20

... change the font size of the label object, the height of the label is automatically adjusted for you Actually, I am not a big fan of automatic sizing of labels For that reason, I turn off the auto-sizing ... in the Source window by clicking the white sizing boxes that appear on the ends and corners of the label object You can increase the width of the label by clicking the middle sizing box on the ... download The examples in this book work with either the Professional or Express versions of C# After those requirements, the system you use is a matter of taste The source code for the samples...

Ngày tải lên: 15/02/2014, 07:20

... either the surname of the family or the number of the house To distinguish data in different areas of memory, we could give the data a name or use the numeric memory address of the first byte of ... subdirectory of the avi package The second pathway is signified by c:\, which is the root directory of the C drive The computer will search all the subdirectories of the root directory to find the subdirectory ... stored in the computer memory in two parts, a mantissa (the fractional part) and an exponent (the power to which the base of the number must be raised in order to give the correct value of the number...

Ngày tải lên: 05/03/2014, 13:20

... from the logic of how the objects of the system work together to start the car You just initiate the sequence of events by executing the start method of the ignition object with the key You then ... dashed line represents the lifeline of the object Rectangles on the lifeline represent activations of the object The height of the rectangle represents the duration of the object’s activation ... the functional requirements of the system • Identify the boundaries of the system • Identify the users of the system • Describe the interactions between the system and the external users • Establish...

Ngày tải lên: 14/03/2014, 23:20

... access, the data members of a class are normally declared in the private section s The public part constitutes the interface to objects of the class s The data members and functions declared in the ... together as a single unit s Class consists of not only data elements but also functions, which operate on the data elements s All the variables and the functions declared in a class, whether in the ... Grouping of objects that have the same properties, common behaviour and common relationships s The term class is an abbreviation of “class of objects” • Example, A class of persons, class of animals,...

Ngày tải lên: 16/03/2014, 01:20

... gives the address of the object, which was used to invoke the member function Whenever a member function is called, the compiler assigns the address of the object which invoked the function, to the ... copy of the data members of the class All the objects in a given class use the same member functions The member functions are created and placed in memory only once - when they are defined in the ... Oriented Scope resolution operator (Contd.) The left-hand operator of :: must be the name of the class Only the scope operator identifies the function as a member of a particular class Is also used to...

Ngày tải lên: 16/03/2014, 01:20

... in the preparation of this book to ensure the accuracy of the information presented However, the information contained in this book is sold without warranty, either express or implied Neither the ... find a number of styles of text that distinguish between different kinds of information Here are some examples of these styles, and an explanation of their meaning [] Introduction There are three ... (well, they are called keys)? Objects are much more than arrays because they contain some methods inside them They can either hide them or expose them, which are not possible in arrays The object...

Ngày tải lên: 22/03/2014, 23:20