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SetValidate()

SetValidate()

Using MODIFY() function. When a DataWindow is based on a join of multiple tables, we can update all of those tables by modifying attributes DataWindow.Table, UpdateTable and column attributes Update and KEY using Modify() function. For example, if the data initially came from DEPARTMENT and EMPLOYEE tables, and DEPARTMENT table was specified as an Update Table when we PAINTED the DataWindow, we need to:

1. Update the DEPARTMENT table using the Update() function:

iRet = dw_1.Update (TRUE (AcceptText(), FALSE (ResetBuffer))

2.Modify the Update CHARACTERISTICS of the DataWindow to point to the Employee table:

IF iRet = 1 THEN
dw_1.Modify(“Dep_id.Update = NO”) dw_1.Modify(“Dep_name.Update = NO”)
dw_1.Modify(“Dep_id.Key = NO”)
dw_1.Modify(“DataWindow.Table.Updatetable = ‘employee’”)
dw_1.Modify(“Dep_id.Update = YES”)
dw_1.Modify(“Dep_name.Update = YES”)
dw_1.Modify(“Dep_id.Key = YES”)
dw_1.Update()
END IF

Using Modify() function. When a DataWindow is based on a join of multiple tables, we can update all of those tables by modifying attributes DataWindow.Table, UpdateTable and column attributes Update and Key using Modify() function. For example, if the data initially came from DEPARTMENT and EMPLOYEE tables, and DEPARTMENT table was specified as an Update Table when we painted the DataWindow, we need to:

1. Update the DEPARTMENT table using the Update() function:

iRet = dw_1.Update (TRUE (AcceptText(), FALSE (ResetBuffer))

2.Modify the Update characteristics of the DataWindow to point to the Employee table:

IF iRet = 1 THEN
dw_1.Modify(“Dep_id.Update = NO”) dw_1.Modify(“Dep_name.Update = NO”)
dw_1.Modify(“Dep_id.Key = NO”)
dw_1.Modify(“DataWindow.Table.Updatetable = ‘employee’”)
dw_1.Modify(“Dep_id.Update = YES”)
dw_1.Modify(“Dep_name.Update = YES”)
dw_1.Modify(“Dep_id.Key = YES”)
dw_1.Update()
END IF

NO. After we have shared 2 DataWindows, we have to SHARE all DropDowns as well. First, we have to GET the reference for the Child DATAWINDOW using GetChild() function and then do sharing by using ShareData() function.

DataWindowChild dwc_1, dwc_2
dw_1.getchild(“EMPLOYEE”, dwc_1)
dwc_1.SetTransObject(sqlca)
dwc_1.Retrieve()
dw_2.getchild(“employee”, dwc_2)
dwc_1.ShareData(dwc_2)

NO. After we have shared 2 DataWindows, we have to share all DropDowns as well. First, we have to get the reference for the Child DataWindow using GetChild() function and then do sharing by using ShareData() function.

DataWindowChild dwc_1, dwc_2
dw_1.getchild(“employee”, dwc_1)
dwc_1.SetTransObject(sqlca)
dwc_1.Retrieve()
dw_2.getchild(“employee”, dwc_2)
dwc_1.ShareData(dwc_2)

Yes, using DataWindow’s CONTROL ATTRIBUTE “DataObject”. DataWindow control has the attribute DataObject. If we WANT to change an associated DataWindow object at RUNTIME we need to put a line in the script that changes the value of the DataObject attribute.

For example:

dw_1.DataObject = “d_name”

Yes, using DataWindow’s control attribute “DataObject”. DataWindow control has the attribute DataObject. If we want to change an associated DataWindow object at runtime we need to put a line in the script that changes the value of the DataObject attribute.

For example:

dw_1.DataObject = “d_name”

The CREATE() function MUST be followed by SetTransObject() function because Create() DESTROYS any previous association between the DATAWINDOW and a transaction object. Then, we can issue a Retrieve().

The Create() function must be followed by SetTransObject() function because Create() destroys any previous association between the DataWindow and a transaction object. Then, we can issue a Retrieve().

We use SyntaxFromSQL() and Create() 

functions:

SQLCA.SyntaxFromSQL(select string, presentation string, Error string)
dw_1.Create(SYNTAX, Error string)
dw_1.SetTransObject(SQLCA)
dw_1.Rerieve()

To create a DataWindow dynamically we have to:

1. build a string to hold a SQL Select statement;
2. build a string to specify the presentation characteristics of the DataWindow object;
3. ASSOCIATE the syntax and description with an existing DataWindow control;
4. associate the DataWindow control with a transaction object, and perform a retrieval.

The DataWindow that is created exists only for the life of the DataWindow control, unless we use the LibraryImport() function to save it in a library. Dynamic DW objects allow US to create and modify DW objects on the fly. To create a DW dynamically, use the Create() function.

Creating takes two arguments: the NAME of the DataWindow object that will be replaced by the new DW object, and the syntax for creating the new DW object. We can create the DW object syntax in a script, but it is easier to use the SyntaxFromSQL() to generate the syntax from a SELECT statement.

We use SyntaxFromSQL() and Create() 

functions:

SQLCA.SyntaxFromSQL(select string, presentation string, Error string)
dw_1.Create(syntax, Error string)
dw_1.SetTransObject(SQLCA)
dw_1.Rerieve()

To create a DataWindow dynamically we have to:

The DataWindow that is created exists only for the life of the DataWindow control, unless we use the LibraryImport() function to save it in a library. Dynamic DW objects allow us to create and modify DW objects on the fly. To create a DW dynamically, use the Create() function.

Creating takes two arguments: the name of the DataWindow object that will be replaced by the new DW object, and the syntax for creating the new DW object. We can create the DW object syntax in a script, but it is easier to use the SyntaxFromSQL() to generate the syntax from a SELECT statement.

In a .PBL FILE.

In a .PBL file.

The EASIEST way to create a report that has a single GROUP is to select the Group PRESENTATION style from the NEW DATAWINDOW dialog box.

The easiest way to create a report that has a single group is to select the Group presentation style from the New DataWindow dialog box.

The DBErrorCode() function (not SQLCA.SQLCode) checks the results of Database access PERFORMED by a DATAWINDOW. We CHECK SQLCA.SQLCode after explicitly issuing EMBEDDED SQL STATEMENTS, such as Commit.

The DBErrorCode() function (not SQLCA.SQLCode) checks the results of Database access performed by a DataWindow. We check SQLCA.SQLCode after explicitly issuing embedded SQL statements, such as Commit.

• DISPLAYING DATA.
• ENTERING data.
• SCROLLING.
• REPORTING.

DataWindow CONTROL is a CONTAINER for a DW OBJECT and is placed on the window. DW control has attribute and functions. DataWindow object is a PB object which has connection to database and GUI. DW object has attributes. DataWindow object represents the data source. It encapsulates your database access into a high level object that handles the retrieval and manipulation of data use for displaying data and capturing user input. DataWindow object consist of :

• data intelligence (perform test VALIDATION rules)
• user interface (presentation style)

It is used to display data or capture user input. DW is an object that we use to retrieve, present and MANIPULATE data from a relational DB or other data source in an intelligent way. (The DW control is the container for the DW object. The DW object is created using the DW painter; a DW control is placed on the window. A DW object has attributes. A DW control has attributes and functions. A DW object represents the data source. It encapsulates your database access into a high level object that handles the retrieval and manipulation of data. It is used for displaying data and capturing the user input. A DW object consists of data intelligence (performs test validation rules) and user interface (presentation style).

DataWindow control is a container for a DW object and is placed on the window. DW control has attribute and functions. DataWindow object is a PB object which has connection to database and GUI. DW object has attributes. DataWindow object represents the data source. It encapsulates your database access into a high level object that handles the retrieval and manipulation of data use for displaying data and capturing user input. DataWindow object consist of :

It is used to display data or capture user input. DW is an object that we use to retrieve, present and manipulate data from a relational DB or other data source in an intelligent way. (The DW control is the container for the DW object. The DW object is created using the DW painter; a DW control is placed on the window. A DW object has attributes. A DW control has attributes and functions. A DW object represents the data source. It encapsulates your database access into a high level object that handles the retrieval and manipulation of data. It is used for displaying data and capturing the user input. A DW object consists of data intelligence (performs test validation rules) and user interface (presentation style).

We can define validation rules in the DATAWINDOW PAINTER. We can use the SetValidate() function in a script to SET validation rules DYNAMICALLY (at run TIME) in a script for DW.

We can define validation rules in the DataWindow painter. We can use the SetValidate() function in a script to set validation rules dynamically (at run time) in a script for DW.

ScrollToRow()

ScrollToRow()

Just once when we define the DW control. If we CHANGE the association of a DATAWINDOW object with a DataWindow control in a script, we MUST re-issue the SetTransObject () before the NEXT retrieval or update.

Just once when we define the DW control. If we change the association of a DataWindow object with a DataWindow control in a script, we must re-issue the SetTransObject () before the next retrieval or update.

In N-up style, we can ALSO have information from SEVERAL ROWS in the DATABASE across the page, but the information is not printed on labels.

In N-up style, we can also have information from several rows in the database across the page, but the information is not printed on labels.

In the GRID PRESENTATION style, we cannot move columns and headings around as we can in the Tabular presentation style but in Grid presentation style USERS can reorder and RESIZE columns with the MOUSE during execution.

In the Grid presentation style, we cannot move columns and headings around as we can in the Tabular presentation style but in Grid presentation style users can reorder and resize columns with the mouse during execution.

The Tabular PRESENTATION STYLE presents data with the data columns going across the page and headers above each column. As many rows from the database will display at one time as can fit in the DataWindow object. We can reorganize the Tabular presentation style any way we want by moving columns and text. Tabular style is OFTEN used when we want to group data.

The Freeform style presents data with the data columns going down the page and labels next to each column. We can reorganize the default layout any way we want by moving columns and text. Freeform style is often used for data entry form.

The Grid style presents data in a row-and-column format with grid lines separating rows and columns. Everything we place in a grid DataWindow object must fit in one cell in the grid. We cannot move columns and headings around as we can in the Tabular and Freeform styles. But, unlike the others styles, users can reorder and resize columns with the mouse in a grid DataWindow object during execution.

The Label style presents data as labels. We choose this style to create mailing labels or other kinds of labels. If we choose the Label style, we are ASKED to specify the attributes for the label in the Specify Label Specification.

The N-Up style presents two or more rows of data next to each other. It is similar to the Label style. We can have information from several rows in the database across the page, but the information is not printed on labels. The N-Up presentational style is useful if we have periodic data; we can SET it up so each period repeats in a row..

The Group presentation style provides an easy way to create grouped DW objects, where rows are divided into groups, each of which can have statistics calculated for it. It generates a tabular DW that has one group level and some other grouping properties defined. We can customise the DataWindow in the DataWindow painter workspace.

The Composite presentation style allows us to combine multiple DWs in the same object. It is handy if we want to print more than one DataWindow on a page.

The Graph presentation style creates a DataWindow object that is only a graph the underlying data is not displayed. As the data changes, the graph is automatically updated to reflect the new values. We use a graph to enhance the display of information in the DataWindow object such as a tabular or freeform DataWindow.

Crosstab processes all the data and presents the summary information that we have defined for it. We use if we want to analyse data. Crosstab analyses data in a spreadsheet. Instead of seeing a long series of rows and columns, users can look at a Crosstab that summarises the data.

OLE 2.0 presentation style using a process called uniform data transfer; info from PB supported data sources can be sent to an OLE 2.0 server application. The OLE 2-compliant application uses the PB supplied data to formulate a graph, map, a spreadsheet or the like to be displayed in the DW.

RichText presentation style using a RichText DW, you can create letters of other documents by merging info in your DB into a formatted DW. Master word processing oriented features such as headers, footers and multiple fonts are available in an easy-to-use format.

The Tabular presentation style presents data with the data columns going across the page and headers above each column. As many rows from the database will display at one time as can fit in the DataWindow object. We can reorganize the Tabular presentation style any way we want by moving columns and text. Tabular style is often used when we want to group data.

The Freeform style presents data with the data columns going down the page and labels next to each column. We can reorganize the default layout any way we want by moving columns and text. Freeform style is often used for data entry form.

The Grid style presents data in a row-and-column format with grid lines separating rows and columns. Everything we place in a grid DataWindow object must fit in one cell in the grid. We cannot move columns and headings around as we can in the Tabular and Freeform styles. But, unlike the others styles, users can reorder and resize columns with the mouse in a grid DataWindow object during execution.

The Label style presents data as labels. We choose this style to create mailing labels or other kinds of labels. If we choose the Label style, we are asked to specify the attributes for the label in the Specify Label Specification.

The N-Up style presents two or more rows of data next to each other. It is similar to the Label style. We can have information from several rows in the database across the page, but the information is not printed on labels. The N-Up presentational style is useful if we have periodic data; we can set it up so each period repeats in a row..

The Group presentation style provides an easy way to create grouped DW objects, where rows are divided into groups, each of which can have statistics calculated for it. It generates a tabular DW that has one group level and some other grouping properties defined. We can customise the DataWindow in the DataWindow painter workspace.

The Composite presentation style allows us to combine multiple DWs in the same object. It is handy if we want to print more than one DataWindow on a page.

The Graph presentation style creates a DataWindow object that is only a graph the underlying data is not displayed. As the data changes, the graph is automatically updated to reflect the new values. We use a graph to enhance the display of information in the DataWindow object such as a tabular or freeform DataWindow.

Crosstab processes all the data and presents the summary information that we have defined for it. We use if we want to analyse data. Crosstab analyses data in a spreadsheet. Instead of seeing a long series of rows and columns, users can look at a Crosstab that summarises the data.

OLE 2.0 presentation style using a process called uniform data transfer; info from PB supported data sources can be sent to an OLE 2.0 server application. The OLE 2-compliant application uses the PB supplied data to formulate a graph, map, a spreadsheet or the like to be displayed in the DW.

RichText presentation style using a RichText DW, you can create letters of other documents by merging info in your DB into a formatted DW. Master word processing oriented features such as headers, footers and multiple fonts are available in an easy-to-use format.

If we select TABLES that have one or more columns with identical NAMES, the Select painter automatically DISPLAYS the JOIN, assuming equality between the two columns.

If we select tables that have one or more columns with identical names, the Select painter automatically displays the join, assuming equality between the two columns.

DATASTORE is a non-visual DataWindow CONTROL. DataStore used for Background PROCESSING, processing Embeded SQL and Distributed objects.

Background Processing: 

Sometimes we use multiple DataWindow control on the screen to display ONE single report. But those DataWindows are not usable for printing. So we use hidden DataWindow control for printing.

Processing Embedded SQL:

Lot of times we need to use embedded SQL to check whether a particular record is existing in the databse or not. So we can check for the existing record using DataStore.

Distrubuted Objects:

We can use DataStore in the SERVER application when we are developing a distributed application.

DataStore is a non-visual DataWindow control. DataStore used for Background processing, processing Embeded SQL and Distributed objects.

Background Processing: 

Sometimes we use multiple DataWindow control on the screen to display one single report. But those DataWindows are not usable for printing. So we use hidden DataWindow control for printing.

Processing Embedded SQL:

Lot of times we need to use embedded SQL to check whether a particular record is existing in the databse or not. So we can check for the existing record using DataStore.

Distrubuted Objects:

We can use DataStore in the server application when we are developing a distributed application.

PRIMARY BUFFER:

When data is retrieved from the databse by using retrieve() function, it is retrieved into the Primary Buffer and it is the content of this buffer that are displayed in the datawindow.

Powerbuilder always displays the data in datawindow control from the Primary Buffer. Data from other buffers are not visible to the user.

ORIGINAL BUFFER

When user modifies a row in the DataWindow the row in the Primary Buffer is modified and the original value is copied into the Original Buffer from the Primary Buffer. Copies data only when the user modify the row for the first time.

DELTED BUFFER

When the user deletes a row with the DeleteRow() function, rows are transferred from Primary Buffer to DELETED Buffer.

FILTERED BUFFER

When rows are filtered using the SetFilter() function, the filtered rows are display in the DataWindow and don’t MATCH the filterd CONDITIONS are moved to the Filtered Buffer. 

EDIT CONTROL OR DATA BUFFER

Edit DataWindow Control has one edit control. It contains the current column’s data. When the user modify the data in a column modify data is copied in Edit Control Buffer. The modify data on the screen and the content of the Edit Control are same. But the value in the Primary Buffer has the old data.

PRIMARY BUFFER:

When data is retrieved from the databse by using retrieve() function, it is retrieved into the Primary Buffer and it is the content of this buffer that are displayed in the datawindow.

Powerbuilder always displays the data in datawindow control from the Primary Buffer. Data from other buffers are not visible to the user.

ORIGINAL BUFFER

When user modifies a row in the DataWindow the row in the Primary Buffer is modified and the original value is copied into the Original Buffer from the Primary Buffer. Copies data only when the user modify the row for the first time.

DELTED BUFFER

When the user deletes a row with the DeleteRow() function, rows are transferred from Primary Buffer to Deleted Buffer.

FILTERED BUFFER

When rows are filtered using the SetFilter() function, the filtered rows are display in the DataWindow and don’t match the filterd conditions are moved to the Filtered Buffer. 

EDIT CONTROL OR DATA BUFFER

Edit DataWindow Control has one edit control. It contains the current column’s data. When the user modify the data in a column modify data is copied in Edit Control Buffer. The modify data on the screen and the content of the Edit Control are same. But the value in the Primary Buffer has the old data.

• Composite
• Crosstab
• Freeform
• GRAPH
• Grid
• Group
• LABEL
• N-up
• OLE-2.0
• Richtext
• TABULAR

A datawindow object is an object that you use to retrieve, PRESENT and manipulate data from a relational database or other data source(Such as EXCEL worksheet or DBASE file).

RETRIEVES data from a database and present it to the user in a wide variety of styles. 

We can use datawindow OBJECTS in client/server, web-bsed and mult-itier APPLICATIONS.

The report we can create in Infomaker and the Datawindow objects. We can create in POWERBUILDER and the same objects.

A datawindow object is an object that you use to retrieve, present and manipulate data from a relational database or other data source(Such as EXCEL worksheet or DBASE file).

Retrieves data from a database and present it to the user in a wide variety of styles. 

We can use datawindow objects in client/server, web-bsed and mult-itier applications.

The report we can create in Infomaker and the Datawindow objects. We can create in powerbuilder and the same objects.

A DropDownDataWindow BEHAVES a CHILD of the DataWindow Object that CONTAINS it.

A DropDownDataWindow behaves a child of the DataWindow Object that contains it.

• SET PROFILE STRING()
• ProfileString()
• ProfileInt()

INI stands for “initialization”. They are PRIMARILY intended to be a standard format that applications can make use of to hold INFO from one run to the next. Rather than hard-coding the VALUES of transaction properties in SCRIPTS, which is too inflexible for most real-world applications, you’ll want your scripts to read some or all of them from an .INI file. You COULD use PB.INI .INIs are always in the same format:

[Database]
DBMS = Sybase
Database = Video Store DB
User Id =
DB Password =
Log Password =
Server Name =
Log Id=
Lock =
DBParm=ConnectString=‘DSN=VideoStore DB;UID=dba’

INI stands for “initialization”. They are primarily intended to be a standard format that applications can make use of to hold info from one run to the next. Rather than hard-coding the values of transaction properties in scripts, which is too inflexible for most real-world applications, you’ll want your scripts to read some or all of them from an .INI file. You could use PB.INI .INIs are always in the same format:

[Database]
DBMS = Sybase
Database = Video Store DB
User Id =
DB Password =
Log Password =
Server Name =
Log Id=
Lock =
DBParm=ConnectString=‘DSN=VideoStore DB;UID=dba’

HALT : 

Halt statement forces the application to terminate IMMEDIATELY. This is most often used to shut down the application after a SERIOUS error occurred.

HALT CLOSE : 

Halt Close does the same thing but TRIGGERS the application OBJECT’s Close EVENT before terminating.

HALT : 

Halt statement forces the application to terminate immediately. This is most often used to shut down the application after a serious error occurred.

HALT CLOSE : 

Halt Close does the same thing but triggers the application object’s Close event before terminating.

• HALT
• HALT CLOSE
• CLOSE

EVERY PowerBuilder application has the MessageObject and the ErrorObject. ErrorObject is used to report ERRORS during execution. MessageObject to PROCESS messages that are not PowerBuilder-defined EVENTS, and PASS parameters between windows.

Every PowerBuilder application has the MessageObject and the ErrorObject. ErrorObject is used to report errors during execution. MessageObject to process messages that are not PowerBuilder-defined events, and pass parameters between windows.

A structure is a collection of ONE or more RELATED variable of the same or different data types grouped under a single name.

Global:

Not ASSOCIATED with any OBJECTS.

OBJECT Level:

Associated with particular types of windows, menu or user object.

A structure is a collection of one or more related variable of the same or different data types grouped under a single name.

Global:

Not associated with any objects.

Object Level:

Associated with particular types of windows, menu or user object.

USE Handle() FUNCTION. Handle() RETURNS the OBJECT’s name if the object EXISTS.

Use Handle() function. Handle() returns the object’s name if the object exists.

We could do it USING PB function Run(). Run(string{, WindowState}), where string is a string whose value is the filename of the program we WANT to execute. Optionally, the string can CONTAIN one or more PARAMETERS of the program; WindowState (optional) is a value of the WindowState enumerated data type indicating the state in which we want to run the program.

E.g., Run(“c:windowsnotepad.exe”, Maximized!)

We could do it using PB function Run(). Run(string{, WindowState}), where string is a string whose value is the filename of the program we want to execute. Optionally, the string can contain one or more parameters of the program; WindowState (optional) is a value of the WindowState enumerated data type indicating the state in which we want to run the program.

E.g., Run(“c:windowsnotepad.exe”, Maximized!)

OPEN: the user starts application.

IDLE: No mouse or keyboard activity happens in a specified number of seconds SystemError - A serious error occurred during execution.

CLOSE: The user closes the application

ConnectionBegin: In a distributed COMPUTING ENVIRONMENT, occurs on the server when a client establishes a CONNECTION to the server by calling the ConnectToServer function.

ConnectionEnd: In a distributed computing environment, occurs on the server when a client DISCONNECTS from the server by calling the DisconnectServer function.

OPEN: the user starts application.

IDLE: No mouse or keyboard activity happens in a specified number of seconds SystemError - A serious error occurred during execution.

CLOSE: The user closes the application

ConnectionBegin: In a distributed computing environment, occurs on the server when a client establishes a connection to the server by calling the ConnectToServer function.

ConnectionEnd: In a distributed computing environment, occurs on the server when a client disconnects from the server by calling the DisconnectServer function.

LOCAL: Local VARIABLE is a temporary variable only DECLARED in the script itself and they are available only in the script where they were declared, when the script is finished execution the local variable is destroyed.

Instance: Intance variable that belongs to an object and associated with an instance of object. It allows VALUES to be shared between scripts in the same object.

Shared: Shared variable retain their value when an object is closed and opened again.

Global: Global variabl can access anywhere in the application. Can access any object in the application. It has public access level.

Local: Local variable is a temporary variable only declared in the script itself and they are available only in the script where they were declared, when the script is finished execution the local variable is destroyed.

Instance: Intance variable that belongs to an object and associated with an instance of object. It allows values to be shared between scripts in the same object.

Shared: Shared variable retain their value when an object is closed and opened again.

Global: Global variabl can access anywhere in the application. Can access any object in the application. It has public access level.

PassByValue : When an argument is passed by VALUE the FUNCTION can accesses the temperory local COPY of the arguments and can CHANGE the value of the local copy.

PassByRef: When an argument is passed by reference the function can accesses the original value of the argument and can change it directly.

PassbyReadOnly: When an argument is passed by read-only we can’t change its value but we can change the value of the argument but we can’t assign another OBJECT to that object.

PassByValue : When an argument is passed by value the function can accesses the temperory local copy of the arguments and can change the value of the local copy.

PassByRef: When an argument is passed by reference the function can accesses the original value of the argument and can change it directly.

PassbyReadOnly: When an argument is passed by read-only we can’t change its value but we can change the value of the argument but we can’t assign another object to that object.

A user define function is a collection of power script STATEMENTS that perform some PROCESSING.

Two types of user define function :

Global function : Accessible any whare in the application.

Object Level function :Object Level functions are DEFINED for a WINDOW, menu, user object or application object.

A user define function is a collection of power script statements that perform some processing.

Two types of user define function :

Global function : Accessible any whare in the application.

Object Level function :Object Level functions are defined for a window, menu, user object or application object.