Interview Questions.

Top 100+ Datagrid Interview Questions And Answers


Top 100+ Datagrid Interview Questions And Answers

Question 1. What Is The Purpose Of Using Datagrid Control?

Answer :

The DataGrid manipulate is used to display the fields of the table. It is basically associated with the statistics supply this is gift in the column of a desk. 
DataGrid provides the get entry to to the rows that allows the manage to be taken to the file in the records source. 
DataGrid control presents diverse features like editing, selection, deleting, paging and sorting. 
DataGrid control allows the user to jot down the input to deliver the output at the web the front. It can comprise the executable scripts or SQL statements. 
DataGrid control makes use of the validation server control to validate the information rows and columns of the desk.
Question 2. Why Is The Update Strategy Not Preferred To Be Used In Datagrid Control?

Answer :

The update approach is inefficient to provide the updates to the database for every of the grid row. 
The updates sent are not sufficient to expose the changes which are being made each minute/seconds. 
Manual good judgment needs to be up to date to check for the modifications that has taken area between the controls in a particular row in grid. 
Comparisons are tough to make among distinctive datasets and databases that involves a round experience. 
No checking of the database take location to see the updations and changes made in it after some time.
Core Java Interview Questions
Question three. What Are The Ways In Which The Functionalities Can Be Added To Datagrid Control Data Source?

Answer :

DataGrid control allows the person to modify and manage the information without adding the new ones. To upload the capability following matters need to be carried out:
Add a new record within the records source for the grid and assign an ID to the file. 
Put a placeholder values within the homes region for columns and make a column such that it may’t be null. 
Rebind the DataGrid control to the supply thru which the change can be executed. 
Determine the place in which the record will appear on the grid. 
Update the document so as to be automated whilst the user clicks on it or updates a link or a new report is added.
Question 4. Write A Program To Control The Column Width, Height And Alignment Of Datagrid?

Answer :

DataGrid control has the manage over the rows and columns sizes that fits the height and width of the grid. 
AutoGenerateColumns assets has to be False to control the column characteristics and it doesn’t let the column to generate routinely. 
The column width can be created the use of the fashion detail for a specific column. It can also set the width of the element.
The belongings may be set like:

<asp:BoundColumn DataField="title" SortExpression="title" 
<ItemStyle Width="100px"></ItemStyle>

Core Java Tutorial
Question five. What Is The Difference Between Windows Forms And Web Forms Datagrid Control?

Answer :

Web Forms have the collection of pages that carry out the spherical journey for the processing at the server. Whereas, Windows Forms doesn’t perform that properly on the processing the front. 
Web Forms DataGrid manipulate uses less built-in capability, while, Windows Forms uses extra integrated functionality. 
Web Forms DataGrid control doesn’t guide designated master records structure, whereas, Windows Forms helps the records structure. 
Web Forms DataGrid control helps the 2 way binding and the automation is being done for the information, while, Windows Forms doesn’t offer  way binding and manual code need to be written. 
Web Forms permit users to edit simplest one row at a time and doesn’t have aid for sorting and no occasion handles, while, Windows Forms provide all that.
SQL Server 2008 Interview Questions
Question 6. How Is It Possible To Edit The Data In Datagrid?

Answer :

DataGrid offers a manner to edit the facts and set the residences to create a very good person interface. 
DataGrid affords a manner to create an application that provides interactivity through the usage of the set or unset of the strategies like CanUserAddRows, CanUserDeleteRows, CanUserReorderColumns, etc. 
To edit look for the properties that starts with CAN and change it in step with the requirements. 
Adding or editing of a row or information outcomes the collection of the Items that is assigned to the ItemsSource.
Question 7. What Is The Purpose Of External Ienumerables Used In Datagrid?

Answer :

External IEnumerables are used to acquire the collection of Items which can be supplied with the DataGrid. 
The records that is being displayed is usually having outside sources like database connection so DataGrid makes use of an external series object. 
Before collection any records it's far vital to set the ItemsSource property and an object type is created to maintain the facts. 
The example of maintaining the item type is proven under: 

public elegance Person

public string call  set; get;  
public int age  set; get; 
public bool member  set; get; 

Collection of those objects wishes to be created for the listing of them: 

List<Person> myList = new List<Person>();
myList.Add(new Person() call="hi there",age=30,member=actual);
myList.Add(new Person() name="yello",age=25,member=fake);
myList.Add(new Person() call="mello",age=15,member=true);

To show the collection the DataGrid object is used like:


SQL Server 2008 Tutorial ASP.NET Interview Questions
Question eight. Write A Program That Adds Two Columns Binded With The Same Properties And Having Column Headings Using Xaml?

Answer :

Columns can be added in their very own manner via making  specific columns and including them using the characteristic of Column.Add().
The order of the columns isn't always decided by way of the order in which they're proven or stored. To listing the order use of DisplayIndex assets is used. 
To add the columns which can be binded with one another first there may be a want to create the facts and upload the statistics to the items collection. 
XAML is used to instantiate and initialize the two columns and produces the equal result with the in-built function as everyday language. 
<DataGrid Height="50" 
Width="100" >
Binding="Binding Path=name" 
Binding="Binding Path=age

Question nine. What Are The Ways That Properties Can Be Shown In Datagrid?

Answer :

DataGrid indicates the homes inside the shape of columns and every column shop a few fee. 
DataGrid want two columns and each of them is certain to have one property each and that is also one of a kind from one another. 
After creating the 2 columns with the homes the binding need to be executed of those columns to display the statistics. 
The approaches are being shown as:

DataGridTextColumn col1 = new DataGridTextColumn();
col1.Binding = new Binding("call");
DataGridTextColumn col2 = 
new DataGridTextColumn();
col2.Binding = new Binding("age"); 

Hibernate Interview Questions
Question 10. Write A Program To Display The Use Of Multiple Columns In Datagrid?

Answer :

The DataGrid that is used contains the supply to have more than one columns to comprise the information in an easy and ordered manner. 
Every column within the multiple columns is having distinct assets of the gadgets and having series of gadgets. 
The objects are named according to the houses given from get/set properties and the general public records subject in this case can’t be created. 
The application that shows the advent of more than one columns in DataGrid is as follows:

public struct MyData

public string call  set; get; 
public int age  set; get; 

new MyData()call="John",age=25);
new MyData()call = "Jill",age = 29 );

ASP.NET Tutorial
Question eleven. How Does The Binding Work In Datagrid?

Answer :

Binding works on the idea of specifying an item and a belongings to the item that desires to be binded. 
The belongings of the item is saved and retrieved of the records that is involved in binding. 
The series of statistics is being stored in a Data Grid and it's far being supplied by way of the use of CollectionView item that determines all of the gadgets in the series for use as binding. 
CollectionView object factors continually to the present day object this is being sure to a unmarried object and includes unmarried assets. 
The CollectionView is used as a base class and it is able to be used to navigate the object’s cutting-edge function at some point of the gathering. 
The DataContext is being set to one of the gadgets with the paths already described that is being pointed to the binding object assigned to a column.
Angular JS Interview Questions
Question 12. Write A Program To Do Column Sorting, Reordering And Resizing?

Answer :

The statistics grid affords the features on the column which may be taken care of, reordered and resized consistent with the necessities. 
The columns can be enabled and disabled by the usage of the column and row residences in the software.
The homes used in this are as follows:

CanUserReorderColumns // this enables or disables the re-ordering of the column
CanUserResizeColumns // this enables or disables the resizing of the column
CanUserResizeRows // this permits or disables the resizing of the row
CanUserSortColumns // this allows or disables the sorting of the row
The software is proven as: 
<DataGrid ItemsSource="Binding_Products" 
CanUserReorderColumns="True" CanUserResizeColumns="True" 
CanUserResizeRows="False" CanUserSortColumns="True"/>

Core Java Interview Questions
Question thirteen. Write A Program To Show Different Selection Modes In Data Grid?

Answer :

The statistics grid includes the choice modes that may be configured and customized in line with the necessities. 
It consists of the choice modes assets as SelectionMode and SelectionUnit. 
The choice mode of the information grid may be set to either single or prolonged. This manner it defines the choice of one or greater units. 
SelectionUnit is used to outline the scope of 1 selection unit in regarlds to the mobile row by using the statistics as Cell, CellAndRowHeader and FullRow.
The program is as follows:

<DataGrid ItemsSource="Binding_Products" 
SelectionMode="Extended" SelectionUnit="Cell" />

Hibernate Tutorial
Question 14. Write A Program To Manually Define The Columns In .Netgrid?

Answer :

The columns can be manually defined by using the use of the belongings AutoGenerateColumns and trade that belongings to False. 
The columns need to be defined inside the columns collection and within the statistics grid area. 
The software with a view to make the columns is:

DataGridCheckBoxColumn // to outline the boolean values
DataGridComboBoxColumn // to define the enumerable values
DataGridHyperlinkColumn // to define the Uri values
DataGridTemplateColumn // to define the varieties of facts for the cellular template
DataGridTextColumn // to outline textual content values
<DataGrid ItemsSource="Binding_Products" AutoGenerateColumns="False" >
<DataGridTemplateColumn Header="Image" Width="SizeToCells" IsReadOnly="True">
<Image Source="Binding_Image" />

Question 15. What Are The Tasks That Are Involved After The Drop-down List Gets Created?

Answer :

Drop down lists are clean to feature on a template column after which introduced similarly in HTML view. 
There are  duties concerned after populating the drop-down list and they are as follows:
Populate the list this is being used by the net utility or any application according to the requirement. 
Pre-pick out the best object to be introduced on the listing of drop-down this is simply being created. 
The drop-down listing gets created with the sphere already being stuffed and the class being pre-decided on from earlier than that needs to be displayed in the beginning.
Javascript Advanced Interview Questions
Question 16. Explain The Procedure To Display An Editable Drop-down List?

Answer :

To show an editable drop-down listing it calls for:

Template column that is gift inside the Grid and an item of ItemTemplate that consist of controls like statistics-certain.
Use of Label controls that produces the modern-day cost of the sector gift inside the document. 
Adding of the drop down list takes location by way of the usage of the item EditItemTemplate. This item adds a column within the template and the property may be customized in keeping with the requirement. 
DropDownList control may be taken from the EditItemTemplate property editor and adjustments being made into it to represent it on the net front. 
The template column of the drop down listing can be delivered to HTML view.
Javascript Advanced Tutorial
Question 17. What’s The Difference Between The System.Internet.Ui.Webcontrols.Datagrid And System.Home windows.Bureaucracy.Datagrid?

Answer :

System.Web.UI.WebControls.DataGrid doesn’t have the inherited support for the grasp data structure this is special. Whereas, the guide is provided, for the inherited statistics shape this is used in System.Windows.Forms.DataGrid. 
System.Web.UI.WebControls.DataGrid doesn’t provide the two way data writing and binding help. Whereas, System.Windows.Forms.DataGrid affords a  manner binding of records, supply. 
System.Web.UI.WebControls.DataGrid offers manual records access and lets in most effective the editing of 1 row at a time in the Grid. Whereas, System.Windows.Forms.DataGrid offers top customization options with the Web Form features. 
System.Web.UI.WebControls.DataGrid inherits the help for the sorting and managing of the order to type out the grid contents. Whereas, System.Windows.Forms.DataGrid provides the binding and sorting of the grid contents to any object.
Windows Communication Foundation (WCF) Interview Questions
Question 18. What Is The Procedure Followed To Add Attributes In <tr> Tag?

Answer :

To upload the attribute to <tr> tag fist DataGridItem item is being intitialized. 
DataGridItem represents the row within the DataGrid manage and it allows in adding the characteristic to the tag. 
The DataGridItemEventArgs object is used to get the DataGridItem object that is exceeded into the event handler.
The AttributeCollection.Add technique is used for DataGridItem object to add the attribute to the <tr> tag that stores the collection of the gathering of the GridItem. 
The addition of the characteristic to the tag permits it to be represented within the internet web page or web page according to the requirements.
SQL Server 2008 Interview Questions
Question 19. How Can The Appearance Be Controlled In Datagrid?

Answer :

The appearance may be managed via using the attributes and including them the use of the programming. 
The tags that can be used are <td> and <tr> tags, that lets in the rendering by using having the manage on the browser and the attributes which can be used on this. 
Attributes can be used in the occasion handler for the OnItemCreated or OnItemDataBound event.
The characteristic if want to be delivered then a TableCell gadgets need to, be created that represents the mobile in DataGrid. 
The DataGridItemEventArgs item is handed to the occasion handler to be used with the TableCell object and use of AttributeCollection.Add method allow the addition of attributes inside the tags.
Windows Communication Foundation (WCF) Tutorial
Question 20. What Are The Different Types Of Columns That Exist In Datagrid?

Answer :

The one of a kind column kinds utilized in DataGrid are as follows:

BoundColumn: this type is used to show the field in a records source. The field includes an object inside the form of textual content. This is the default column kind in DataGrid manage. 
ButtonColumn: this kind is used to display the column that consists of editing instructions used within the column. 
HyperLinkColumn: this type displays the content material of object in the column as a link. The content may be inside the shape of a textual content or it may have an association with different fields. 
TemplateColumn: this type presentations the object in accordance the template and it additionally allow the introduction of custom controls for the templates.
Version manipulate Interview Questions
Question 21. What Is Dataset Object? Explain The Various Objects In Dataset.?

Answer :

The DataSet object is a disconnected garage.
It is used for manipulation of relational information. 
The DataSet is filled with facts from the shop
We fill it with facts fetched from the facts store. Once the work is achieved with the dataset, connection is reestablished and the adjustments are contemplated returned into the shop.
Dataset has a group of Tables which has DataTable collection which in addition has DataRow DataColumn items collections. 
It also has collections for the number one keys, constraints, and default values known as as constraint series. 
A DefaultView object for every desk is used to create a DataView object based at the desk, in order that the data may be searched, filtered or in any other case manipulated even as displaying the statistics.
Question 22. Difference Between Dataset And Datareader.?

Answer :


DataSet item can include multiple rowsets from the equal facts supply as well as from the relationships among them.
Dataset is a disconnected structure
Dataset can persist information.

DataReader offers ahead-most effective and read-only get entry to to facts.
Datareader is hooked up structure
Datareader can't persist facts.
Question 23. Ado.Net Code Showing Dataset Storing Multiple Tables?

Answer :

Declare and initialize database connection item with appropriate connection string.
Create a DataAdapter and a Dataset item.
Using fill method of the DataAdapter object, load the statistics into the Dataset Object.
Change the adapter's SELECT command. 
Create the EmpDetail table. 
Add each tables to a single dataset. 
Display the data using information binding characteristic of controls like Datagrid or Datalist.
Dim m_adptEmp As SqlDataAdapter:

Private Sub Page_Load(ByVal sender As System.Object, _ByValeAsSystem.EventArgs)HandlesMyBase.Load<BR> DimEmpConnAsNewSqlConnection_<BR> ("server=(nearby);database=Employees;Trusted_Connection=yes")
     m_adptEmp = New SqlDataAdapter("pick out * from Emp", EmpConn)
     Dim dsEmp As New DataSet
     m_adptEmp.Fill(dsEmp, "Emp")
     adptEmp.SelectCommand.CommandText = "SELECT * FROM EmpDetail"
     Dim EmpDetail As New DataTable("EmpDetail")
     DataGrid1.DataSource = dsEmp.Tables("Emp").DefaultView
End Sub

Advanced C# Interview Questions
Question 24. What Tag Do You Use To Add A Hyperlink Column To The Datagrid?

Answer :


ASP.NET Interview Questions
Question 25. Difference Between Datagrid, Datalist And Repeater.?

Answer :


They are all ASP.NET statistics Web controls.

They have common houses like: 

DataSource Property
DataBind Method
When the DataSource Property of a Datagrid is assigned to a DataSet then each DataRow present inside the DataRow Collection of DataTable is assigned to a corresponding DataGridItem.



The HTML code generated has an HTML TABLE element created for the particular DataRow and is a tabular illustration with Columns and Rows. Datagrid has a in-constructed aid for Sort, Filter and paging the Data. 


An Array of Rows and based totally on the Template Selected and the RepeatColumn Property value The wide variety DataSource records that seem in line with HTML

Repeater Control:

The Datarecords to be displayed depend upon the Templates detailed and the simplest HTML generated hence. Repeater does now not have in-constructed assist for Sort, Filter and paging the Data.

Question 26. In Datagrid, Is It Possible To Add Rows One By One At Runtime. That Means After Entering Data In One Row Next Row Will Be Added?

Answer :

Yes, for this you need to use datatable and after placing the primary row in datatable You have to bind that datatable to the grid and next time , first you need to upload the row in datatable and next bind it to datagrid. Preserve on doing. You must maintain the datatable kingdom.

Asp Dot Net Mvc 4 Interview Questions
Question 27. Why Can Not I Add An Entry Via The Grid For A Table Containing A Clob Column?

Answer :

In older versions of TOAD, the grid is confined to adding/enhancing CLOB's for present information. This have to be running in TOAD 7.6. Note, however, that since TOAD does now not support Unicode databases, that there are often errors while viewing CLOB data within the records grids for databases with Unicode character sets.

Hibernate Interview Questions
Question 28. How Do I Copy A Whole Row Or Multiple Rows Of Data?

Answer :

To reproduction one row of facts, positioned your cursor in a mobile inside the grid and press Ctrl+Insert. This will replica the row and its column headers to the clipboard. To copy more than one rows of information, right-click within the grid and choose "Allow multiselect". Use Shift-Click to select a couple of adjoining rows, or use Ctrl+Click to choose character, non-adjacent rows. Press Ctrl+C. This will reproduction all of the rows and their column headers to the clipboard. To replica a unmarried cell's facts, turn off "Allow multiselect". Click on the mobile you want to copy and press Ctrl+C. 

The following table gives details of what takes place with the diverse copy keys and multi-pick out options. 

Multi-Select OFF Multi-Select ON 


One Cell Highlighted Cell most effective Cell best Row plus headings Cell handiest Cell Only Row plus headings 

Many Cells(rows) highlighted N/A N/A N/A All highlighted rows plus headings All highlighted rows plus headings All highlighted rows plus headings

Question 29. How Can I View The Chinese And Japanese Character Sets Through Toad?

Answer :

Reset NLS_LANG in your Client device to AMERICAN_AMERICA.JA16SJIS to view Japanese and AMERICAN_AMERICA.ZHT16BIG5 to view Chinese. Then change the font script for every language by using proper clicking at the facts and deciding on Fonts pick Arial Unicode MS because the Font. This adjustments the script to Japanese for Japanese characters or to ChineseBig5 for Chinese.

Asp Dot Net Mvc Interview Questions
Question 30. How To Add Datetime Control In Ormal Datagrid Server Control?

Answer :

cvv using template column we can thoroughly add date time manipulate as infant control.

Question 31. How To Refresh The Data In Datagrid Automatically?

Answer :

For clean facts in information grid control we will use chasing approach.

Question 32. How Do You Customize The Column Content Inside The Datagrid?

Answer :

If you want to customize the content material of a column, make the column a template column. Template columns paintings like item templates inside the DataList or Repeater manipulate, except that you are defining the format of a column as opposed to a row.

Question 33. How Do You Apply Specific Formatting To The Data Inside The Cells?

Answer :

You cannot specify formatting for columns generated whilst the grid's AutoGenerateColumns assets is about to true, most effective for bound or template columns. To layout, set the column's DataFormatString belongings to a string-formatting expression appropriate for the statistics kind of the statistics you are formatting.

Angular JS Interview Questions
Question 34. How Do You Hide The Columns?

Answer :

One manner to have columns seem dynamically is to create them at design time, after which to hide or display them as wished. You can do that by way of placing a columnï's Visible belongings.

Question 35. How Do You Display An Editable Drop-down List?

Answer :

Displaying a drop-down list requires a template column inside the grid. Typically, the ItemTemplate carries a manipulate inclusive of a facts-bound Label control to expose the modern-day price of a field within the document. You then add a drop-down listing to the EditItemTemplate.

In Visual Studio, you may upload a template column within the Property builder for the grid, and then use popular template editing to dispose of the default TextBox manage from the EditItemTemplate and drag a DropDownList manipulate into it alternatively. Alternatively, you can upload the template column in HTML view.

After you have created the template column with the drop-down listing in it, there are  responsibilities. The first is to populate the listing. The 2nd is to preselect the right object inside the listing � as an instance, if a book�s genre is about to �fiction,� whilst the drop-down listing presentations, you regularly need �fiction� to be preselected.

Question 36. How Do I Change The Grid Popup Editor Font?

Answer :

Another one from the listing. Herald asked > I modified the font for the DATA Grids, so I could take a look at Unicode. Now I see the chosen font inside the datagrid, but if I open the popup editor it nevertheless offers the vintage font. Is it possible to change this font also, I failed to locate it in the alternatives, or should you are making the grid popup editor font the same as the information grid font.

After lots looking, Brad provided the following apparent LOL solution :

*Go to View → Toad Options → Editor → Behavior.
*In the Languages phase, select "Plain Text" from the dropdown and click the Edit ... Button subsequent to the dropdown.
*Go to the Highlighting tab and click on the "custom font" button.
*Choose your font and OK your way out.

Javascript Advanced Interview Questions
Question 37. Why Can Not I Set A Style In My Xls Saveas Exports Of Datagrid Data?

Answer :

Try upgrading to the present day release of TOAD, as we've got acquired an up to date XLS issue. If you're nonetheless experiencing the trouble, you may do that: FORMAT ? CELLS ? NUMBER TAB ? Change to Currency, Percentage, and so forth.

Question 38. How Can I See Timestamp And Interval Data?

Answer :

TOAD 7.Five and up can display TIMESTAMP and INTERVAL facts in its records grids in case you are the use of a 9.Zero.1 or better Oracle patron. TOAD nine.Zero.1 helps TIMESTAMP and INTERVAL facts in its "run as script" characteristic. TOAD variations 7.4 and previous do not assist TIMESTAMP and INTERVAL information because of a hindrance of their statistics layer. 

To see timestamp/intervals within the "datatype" drop down within the Create/Alter Table window, and within the "Add Column" window, visit alternatives ? Datatypes, and make sure "Include Timestamp/Interval Types" is checked.

Question 39. How Can I See Nested Object Data?

Answer :

TOAD 7.Five and up can display nested object type records in popups from the facts grids in case you are the use of an eight.0 or higher Oracle patron. Right-click on at the cell that should incorporate the statistics and select "Popup editor". TOAD 9.Zero.1 now helps nested object information in its "run as script" characteristic. TOAD versions 7.Four and previous do no longer help nested item information due to a predicament in their facts layer.

Question 40. How Can I See The Data In Nested Tables?

Answer :

TOAD 7.Five and up can show nested desk facts in popups from the records grids if you are the use of an 8.0 or better Oracle customer. The nested table records will seem inside the grid cellular as "(DATASET)". Right-click over this cellular and select "Popup editor". TOAD 9.Zero.1 now helps nested table facts in its "run as script" feature. TOAD variations 7.4 and former do no longer aid nested table statistics due to a difficulty in their information layer.

Windows Communication Foundation (WCF) Interview Questions
Question 41. What Is A Datagrid Or Grid View?

Answer :

The DataGrid Web server manipulate is a effective device for displaying records from a records source. It is simple to use; you can show editable records in a expert-looking grid by means of setting only a few residences. At the equal time, the grid has an advanced object version that provides you with amazing flexibility in how you show the information.

Question 42. What Is The Difference Between The System.Internet.Ui.Webcontrols.Datagrid And And System.Windows.Paperwork.Datagrid?

Answer :

The Web UI manipulate does now not inherently help grasp-detail facts structures. As with other Web server controls, it does now not aid two-way data binding. If you want to replace statistics, you ought to write code to do that your self. You can best edit one row at a time. It does now not inherently help sorting, even though it increases events you could deal with for you to kind the grid contents. You can bind the Web Forms DataGrid to any object that helps the IEnumerable interface.

The Web Forms DataGrid manipulate supports paging. It is simple to customize the advent and format of the Web Forms DataGrid control compared to the Windows Forms one.

Version manage Interview Questions
Question 43. How Do You Check Whether The Row Data Has Been Changed?

Answer :

The definitive way to decide whether a row has been dirtied is to handle the changed event for the controls in a row. For instance, in case your grid row incorporates a TextBox control, you may reply to the control�s TextChanged event. Similarly, for take a look at boxes, you could reply to a Checked Changed event. In the handler for these events, you maintain a listing of the rows to be updated. Generally, the satisfactory method is to song the number one keys of the affected rows. For example, you could hold an ArrayList item that includes the primary keys of the rows to update.

Question forty four. Why Can Not I Add A New Record By Hitting The Down Arrow Key In The Data Tab?

Answer :

Please upgrade your reproduction of TOAD to at least version 7.Four.0.3. This functionality has been restored.

Question 45. What Is The Oci Buffer Array Size Option For In The View - Options - Oracle - General Section?

Answer :

After a SELECT question is accomplished, we must retrieve the rows from the Oracle server in your PC. We do no longer retrieve the rows suddenly, nor will we retrieve them one by one (until there is a LONG or LOB column worried). We retrieve the rows in blocks. The quantity of rows retrieved in each block is the quantity of rows you specify with "OCI Array Buffer Size".

TOAD defaults to 25 because SQL*Plus defaults to 25. In my opinion, an top of the line putting is more like 500 or 1000. Here is why: If your dataset has 1,000 rows, and your OCI Array Buffer size is set to twenty-five, then TOAD has to make 40 (that's one thousand / 25) spherical trips across the network to retrieve all the rows. So you could at once see why 500 or 1000 is higher. The handiest drawback to a higher placing of OCI Array Buffer Size is that TOAD need to allocate reminiscence to hold that many rows previous to every fetch. If that many rows are simply fetched, there's no loss. On the other hand, if no longer that many rows are retrieved, then we allotted a few memory that is not going to be released till the cursor is freed. Luckily, this is a trivial amout of memory, in the grand scheme of things.

Question forty six. Explain My String Data Is All Coming Out As Question Marks?

Answer :

We have located that this happens when the database individual set is WE8ISO8859P1, and the Oracle purchaser is nine.2.0.1. This is an Oracle bug, and upgrading your patron to nine.2.0.4 or higher need to remedy the hassle. In some other case, please generate a TOAD Support Bundle from the Help menu and let us recognise what you are seeing.