A Gantt chart allows you to effectively plan your complex projects. It enables you to plan all of your tasks in one place and helps you work out the minimum delivery time for your project and schedule when the right people are available to complete it. Gantt chart starts by listing all the tasks you need to complete to finish your project. You also need to specify the earliest date you can start each activity, how long you think each will take and whether any of them are dependent on the completion of other activities.
Data Workshop
To understand the functionality of this chart, you need to create a
table and populate it with relevant data. For this purpose, you will use Oracle
APEX's Data Workshop utility. The Data Workshop utility located under SQL Workshop enables
you to load and unload text, DDL, and spreadsheet data
to and from the database. You can load or unload XML files or delimited-field text files (such as
comma-delimited (.csv) or tab-delimited files). You can also load data by
copying and pasting from a spreadsheet. During loading and unloading process
you can skip columns you do not need in your table. The utility allows you to
load data into an existing table or create a new table from the loaded data.
When loading into a new table, column names can be taken from the loaded data.
Each time you load data from a file, file details are saved in a Text Data Load
Repository. You can access these files from within the repository at any time.
Note that the wizards load and unload table data only, they do not load or unload other kinds of schema objects.
Download the scripts used in this exercise.
Execute the following steps to create a new table and load it with
relevant data from a csv file.
1. Create
a table named Project_Table using Project_Table.sql
script provided in the book code. Open SQL
Workshop | SQL
Commands (A). Copy and then paste the CREATE TABLE
statement from the script file (Project_Table.sql) into
the command area (B), and then click the Run button (C), as shown in the
following screen shot.
2. Click SQL Workshop | Utilities | Data Workshop to access the Data Load/Unload page.
3. On
the Data Workshop page, click the Load Data button.
4. On
the Load Data page,
select the Upload a File tab, and
click the Choose File button. In the
Open dialog box, select Project_Table.csv
file from downloaded folder,
and click Open.
5. On
the next screen, click the Existing
Table option (A), select the PROJECT_TABLE
(B), and click the Load Data button (C). The database column names and
columns in the data can be viewed in the Preview
section.
If everything goes well, the next screen appears with the message "Data in table PROJECT_TABLE appended with 73
new rows!". Click the View Table button at the bottom to complete the
process.
Create Gantt Chart
Execute the following instructions to create a new page for the Gantt Chart:
1. Click
Create Page in the main App Builder interface.
2. Click
the Chart option.
3. On Chart Type screen, choose Gantt.
4. Fill in the next couple of screens as follows and then click Next.
5. On the
Source screen, choose SQL Query
for Source Type, and enter the
following query in the SQL Query box. Click Next to proceed.
SELECT task_name task_name,
id
task_id,
start_date
task_start_date,
end_date
task_end_date,
decode(status,'Closed',1,'Open',0.6,'On-Hold',0.1,'Pending',0)
status,
(select
min(start_date) -5 from project_table) gantt_start_date,
(select
max(end_date) from project_table)
gantt_end_date
FROM project_table
ORDER BY id ASC
6. Fill
in the Column Mapping screen as illustrated in the following figure:
The
following table provides details of the parameters:
|
Start Date
Column |
Select the column name to be used for defining the start date of the
Gantt chart. |
|
End Date
Column |
Select the column name to be used for defining the end date of the
Gantt chart. |
|
Task ID |
Select the column name to be used for defining the task ID on the Gantt
chart. |
|
Task Name |
Select the column name to be used for defining the task name on the Gantt
chart. |
|
Task Start
Date |
Select the column name to be used for defining the task start date
on the Gantt chart. |
|
Task End
Date |
Select the column name to be used for defining the task end date on
the Gantt chart. |
7. Click
Create to complete the page creation
process.
8. In
Page Designer,
click on Series 1 and set Progress (under Column Mapping) to Status.
The Status column defines the task
progress on the Gantt chart.
9. Click
Save and Run page button to test
your work.
Press and hold the Ctrl key, and move the mouse wheel upward to enable
the zoom buttons (A). Keep clicking the Zoom Out icon unless it is grayed out. The
Gantt chart, as illustrated in
the following screenshot, displays the overall progress of a project. Same-day
tasks are shown in diamond shapes, completed tasks are represented in dark
blue, while remaining tasks are displayed in light blue colors. Hovering the mouse
pointer over a bar shows details of that particular task.
