Union Operator Sample

Contents

Running Union.sbapp in StreamBase Studio
Running Union.sbapp in Terminal Windows
Importing This Sample into StreamBase Studio
Sample Location

The Union operator sample uses a Union operator to interleave trades from a Reuters feed and the Interactive Data PlusFeed (formerly Comstock). The input streams contain schemas with the fields Symbol, PricePS (per share), Time, and FeedID.

Running Union.sbapp in StreamBase Studio

In the Package Explorer, double-click to open the Union.sbapp application. Make sure the application is the currently active tab in the EventFlow Editor.
Click the Run button. This opens the SB Test/Debug perspective and starts the application.
In the Application Output view, select the UnionOut output stream. No output is displayed at this point, but the dequeuer is prepared to receive output. This view eventually shows the output of the application.
In the Manual Input view, select the ComstockIn input stream.
Enter amat, 24, 1, and 0 in the Symbol, PricePS, Time, and FeedID fields, respectively.
Click Send Data, and observe this data appears in the Application Output view:
```
Symbol=amat, PricePS=24.0, Time=1, FeedID=0
```
Select the ReutersIn input stream.
Enter msft, 40, 2, and 1 in the Symbol, PricePS, Time, and FeedID fields, respectively.
Click Send Data, and observe this data appears in the Application Output view:
```
Symbol=msft, PricePS=40.0, Time=2, FeedID=1
```
Enter intc, 24, 3, and 1 in the Symbol, PricePS, Time, and FeedID fields, respectively.
Click Send Data, and observe this data appears in the Application Output view:
```
Symbol=intc, PricePS=24.0, Time=3, FeedID=1
```
Select the ComstockIn input stream.
Enter amat, 23, 4, and 0 in the Symbol, PricePS, Time, and FeedID fields, respectively.
Click Send Data, and observe this data appears in the Application Output view:
```
Symbol=amat, PricePS=23.0, Time=4, FeedID=0
```
Select the ReutersIn input stream.
Enter intc, 22, 5, and 1 in the Symbol, PricePS, Time, and FeedID fields, respectively.
Click Send Data, and observe this data appears in the Application Output view:
```
Symbol=intc, PricePS=22.0, Time=5, FeedID=1
```
Note that the time in this tuple is before the time in the previous tuple. In other words, the Union operator is agnostic to the order of input tuples. Use a Merge operator if you want to order on a field by using a criterion such as time.
When done, press F9 or click the Stop Running Application button.

Running Union.sbapp in Terminal Windows

This section describes how to run the sample in UNIX terminal windows or Windows command prompt windows. On Windows, be sure to use the StreamBase Command Prompt from the Start menu as described in the Test/Debug Guide, not the default command prompt.

Open three terminal windows on UNIX, or three StreamBase Command Prompts on Windows. In each window, navigate to the directory where the sample is installed, or to your workspace copy of the sample, as described above.
In window 1, type:
```
sbd Union.sbapp
```
In window 2, type:
```
sbc dequeue UnionOut
```
No output is displayed at this point, but the dequeuer is prepared to receive output. This window eventually shows the output of the application.
In window 3, type:
```
sbc enqueue
```
The sbc command now waits for keyboard input. Ttype:
```
ComstockIn,amat,24,1,0
```
Observe this line in the dequeue window:
```
amat,24.000000,1,0
```
Type:
```
ReutersIn,msft,40,2,1
```
Observe this line in the dequeue window:
```
msft,40.000000,2,1
```
Type:
```
ReutersIn,intc,24,3,1
```
Observe this line in the dequeue window:
```
intc,24.000000,3,1
```
Type:

ComstockIn,amat,23,5,0

Observe this line in the dequeue window:
```
amat,23.000000,5,0
```
Type:
```
ReutersIn,intc,22,4,1
```
Observe this line in the dequeue window:
```
intc,22.000000,4,1
```
Note that the time in this tuple is before the time in the previous tuple. In other words, the Union operator is agnostic to the order of input tuples. Use a Merge operator if you want to order on a field by using a criterion such as time.
In window 3, type: Ctrl+Z (Windows) or Ctrl+D (UNIX) to exit the sbc session.
In window 3, type the following command to terminate the server and dequeuer:
```
sbadmin shutdown
```

Importing This Sample into StreamBase Studio

In StreamBase Studio, import this sample with the following steps:

From the top menu, click File → Load StreamBase Sample.
Select operator from the Data Constructs and Operators category.
Click OK.

StreamBase Studio creates a single project for the operator samples.

Sample Location

By default, the sample files are installed in:

On Windows: C:\Program Files\StreamBase Systems\StreamBase.n.m\sample\operator
On UNIX: /opt/streambase/sample/operator

When you load the sample into StreamBase Studio, Studio copies the sample project's files to your Studio workspace. StreamBase Systems recommends that you use the workspace copy of the sample, especially on UNIX, where you may not have write access to /opt/streambase. In the default installation, the path to this sample in your Studio workspace is:

UNIX:       
  ~/streambase-studio-n.m-workspace/sample_operator
Windows XP:
  C:\Documents and Settings\username\My Documents\StreamBase Studio n.m Workspace\
      sample_operator
Windows 7 and Windows Vista:
  C:\Users\username\Documents\StreamBase Studio n.m Workspace\
      sample_operator