Setting database preferences

How to set

The way you set connection-related database preferences in PowerBuilder varies,
as summarized in the following table (AutoCommit and Lock are the only
database preferences that you can set in a PowerBuilder application script).

The following sections give the steps for setting database
preferences in the development environment and (for AutoCommit and
Lock) in a PowerBuilder application script.

For more information

For information about using a specific database preference,
see its description in the online Help.

Setting database preferences in the development
environment

There are two ways to set database preferences in the PowerBuilder development
environment on all supported development platforms,
depending on the preference you want to set:

• Set AutoCommit and Lock (Isolation Level) in the
  Database Profile Setup dialog box for your connection
  ADO.NET For ADO.NET, Isolation is a database parameter.
  
• Set all other database preferences in the Database
  Preferences property sheet in the Database painter

Setting AutoCommitand Lock in the database profile

The AutoCommit and Lock (Isolation Level) preferences are
properties of the default Transaction object, SQLCA. For AutoCommit and Lock
to take effect in the PowerBuilder development environment, you must
specify them before you connect to a database.
Changes to these preferences after the connection occurs have no
effect on the current connection.

To set AutoCommit and Lock before PowerBuilder connects to your
database, you specify their values in the Database Profile Setup
dialog box for your connection.

To set AutoCommit and Lock (Isolation Level) in
a database profile:

1. Display the Database Profiles dialog box.

2. Click the plus sign (+) to the left of
   the interface you are using

   or

   Double-click the interface name.

   The list expands to display the database profiles defined
   for your interface.

3. Select the name of the profile you want and click
   Edit.

   The Database Profile Setup dialog box for the selected profile
   displays.

4. On the Connection tab page, supply values for
   one or both of the following:

   • Isolation
     Level If your database supports the use of locking and isolation
     levels, select the isolation level you want to use for this connection
     from the Isolation Level drop-down list. (The Isolation Level drop-down
     list contains valid lock values for your interface.)
   • AutoCommit Mode The setting of AutoCommit controls whether PowerBuilder issues SQL statements outside (True) or
     inside (False) the scope of a transaction. If your database
     supports it, select the AutoCommit Mode check box to
     set AutoCommit to True or clear the AutoCommit Mode check box (the
     default) to set AutoCommit to False.

   For example, in addition to values for basic connection parameters (Server,
   Login ID, Password, and Database), the Connection tab page for the
   following Sybase Adaptive Server Enterprise profile named Sales shows
   nondefault settings for Isolation Level and AutoCommit Mode.

5. (Optional) In PowerBuilder, click the Preview
   tab if you want to see the PowerScript connection syntax generated
   for Lock and AutoCommit.

   PowerBuilder generates correct PowerScript connection syntax
   for each option you set in the Database Profile Setup dialog box.
   You can copy this syntax directly into a PowerBuilder application
   script.

   For instructions, see “Copying SyntaxFromSQL syntax
   from the Preview tab”.

6. Click OK to close the Database Profile Setup dialog
   box.

   PowerBuilder saves your settings in the database profile entry
   in the registry.

Setting preferencesin the Database Preferences property sheet

To set the following connection-related database preferences,
complete the Database Preferences property sheet in the PowerBuilder Database
painter:

• Shared Database Profiles
• Connect to Default Profile
• Read Only
• Keep Connection Open
• Use Extended Attributes
• SQL Terminator
  Character

Other database preferences The Database Preferences property sheet also lets you set
other database preferences that affect the behavior of the Database
painter itself. For information about the other preferences you
can set in the Database Preferences property sheet, see the User’s
Guide
.

To set connection-related preferences in the Database
Preferences property sheet:

1. Open the Database painter.

2. Select Design>Options from the menu bar.

   The Database Preferences dialog box displays. If necessary,
   click the General tab to display the General property page.

3. Specify values for one or more of the connection-related
   database preferences in the following table.

   Table 8-2: Connection-related
   database preferences

   Preference	Description	For details, see
   Shared Database Profiles	Specifies the pathname of the file containing the database profiles you want to share. You can type the pathname or click Browse to display it.	“Sharing database profiles”
   Connect to Default Profile	Controls whether the Database painter establishes a connection to a database using a default profile when the painter is invoked. If not selected, the Database painter opens without establishing a connection to a database.	Connect to Default Profile in online Help
   Read Only	Specifies whether PowerBuilder should update the extended attribute system tables and any other tables in your database. Select or clear the Read Only check box as follows: Select the check box Does not update the extended attribute system tables or any other tables in your database. You cannot modify (update) information in the extended attribute system tables or any other database tables from the DataWindow painter when the Read Only check box is selected. Clear the check box (Default) Updates the extended attribute system tables and any other tables in your database.	Read Only in the online Help
   Keep Connection Open	When you connect to a database in PowerBuilder without using a database profile, specifies when PowerBuilder closes the connection. Select or clear the Keep Connection Open check box as follows: Select the check box (Default) Stays connected to the database throughout your session and closes the connection when you exit Clear the check box Opens the connection only when a painter requests it and closes the connection when you close a painter or finish compiling a script Not used with profile This preference has no effect when you connect using a database profile.	Keep Connection Open in the online Help
   Use Extended Attributes	Specifies whether PowerBuilder should create and use the extended attribute system tables. Select or clear the Use Extended Attributes check box as follows: Select the check box (Default) Creates and uses the extended attribute system tables Clear the check box Does not create the extended attribute system tables	Use Extended Attributes in the online Help
   Columns in Table Display	Specify the number of table columns to be displayed when InfoMaker displays a table graphically. The default is eight.

4. Do one of the following:

   • Click Apply to apply the preference settings to
     the current connection without closing the Database Preferences
     property sheet.
   • Click OK to apply the preference settings to the
     current connection and close the Database Preferences property sheet.

   PowerBuilder saves your preference settings in the database
   section of PB.INI.

Setting AutoCommit and Lock in a PowerBuilder application
script

If you are developing a PowerBuilder application that connects
to a database, you must specify the required connection parameters
in the appropriate script as properties of the default Transaction
object (SQLCA) or a Transaction object
that you create. For example, you might specify connection parameters in
the script that opens the application.

AutoCommit and Lock are properties of SQLCA. As such, they are the only database
preferences you can set in a PowerBuilder script. You can do this
by:

• (Recommended) Copying
  PowerScript syntax for AutoCommit and Lock from the Preview tab
  in the Database Profile Setup dialog box into your script
• Coding PowerScript to set values for the AutoCommit
  and Lock properties of the Transaction object
• Reading AutoCommit and Lock values from an external
  text file

For more about using Transaction objects to
communicate with a database in a PowerBuilder application, see Application
Techniques
.

Copying AutoCommit and Lock syntax from the Preview
tab

The easiest way to specify AutoCommit and Lock in a PowerBuilder application
script is to copy the PowerScript syntax from the Preview tab in
the Database Profile Setup dialog box into your script, modifying
the default Transaction object name (SQLCA)
if necessary.

As you complete the Database Profile Setup dialog box in the
development environment, PowerBuilder generates the correct connection
syntax on the Preview tab for each selected option. Therefore, copying
the syntax directly from the Preview tab ensures that you use the
correct PowerScript syntax in your script.

To copy AutoCommit and Lock syntax from the Preview
tab into your script:

1. On the Connection tab in the Database Profile
   Setup dialog box for your connection, supply values for AutoCommit
   and Lock (Isolation Level) as required.

   For instructions, see “Setting AutoCommit
   and Lock in the database profile”.

   For example, in addition to values for basic connection parameters (Server,
   Login ID, Password, and Database), the Connection tab for the following
   Adaptive Server profile named Sales shows nondefault settings for
   Isolation Level and AutoCommit Mode.

   For information about the DBParm parameters
   for your interface and the values to supply, click Help.

2. Click Apply to save your changes to the current
   tab without closing the Database Profile Setup dialog box.

3. Click the Preview tab.

   The correct PowerScript syntax for each selected option displays
   in the Database Connection Syntax box. For example:

   

4. Select one or more lines of text in the Database
   Connection Syntax box and click Copy.

   PowerBuilder copies the selected text to the clipboard.

5. Click OK to close the Database Profile Setup dialog
   box.

6. Paste the selected text from the Preview tab into
   your script, modifying the default Transaction object name (SQLCA) if necessary.

Coding PowerScript to set values for AutoCommit
and Lock

Another way to specify the AutoCommit and Lock properties
in a script is by coding PowerScript to assign values to the AutoCommit
and Lock properties of the Transaction object. PowerBuilder uses a
special nongraphic object called a Transaction object to
communicate with the database. The default Transaction object is
named SQLCA, which stands
for SQL Communications Area.

SQLCA has 15 properties,
10 of which are used to connect to your database. Two of the connection
properties are AutoCommit and Lock, which you can set as described
in the following procedure.

To set the AutoCommit and Lock properties in a PowerBuilder script:

1. Open the application script in which you
   want to set connection properties.

   For instructions, see the User’s
   Guide
   .

2. Use the following PowerScript syntax to set the
   AutoCommit and Lock properties. (This syntax assumes you are using
   the default Transaction object SQLCA,
   but you can also define your own Transaction object.)

   PowerBuilder

   <b>SQLCA.AutoCommit</b> = <i>value</i>

   1	<b>SQLCA.AutoCommit</b> = <i>value</i>

   PowerBuilder

   <b>SQLCA.Lock</b> = "<i>value</i>"

   1	<b>SQLCA.Lock</b> = "<i>value</i>"

   For example, the following statements in a PowerBuilder script
   use the default Transaction object SQLCA to
   connect to a Sybase Adaptive Server Enterprise database named Test. SQLCA.AutoCommit is
   set to True and SQLCA.Lock is
   set to isolation level 3 (Serializable transactions).

   PowerBuilder

   SQLCA.DBMS = "SYC"

   1	SQLCA.DBMS       = "SYC"

   PowerBuilder

   SQLCA.Database = "Test"

   1	SQLCA.Database   = "Test"

   PowerBuilder

   SQLCA.LogID = "Frans"

   1	SQLCA.LogID      = "Frans"

   PowerBuilder

   SQLCA.LogPass = "xxyyzz"

   1	SQLCA.LogPass    = "xxyyzz"

   PowerBuilder

   SQLCA.ServerName = "HOST1"

   1	SQLCA.ServerName = "HOST1"

   PowerBuilder

   SQLCA.AutoCommit = True

   1	SQLCA.AutoCommit = True

   PowerBuilder

   SQLCA.Lock = "3"

   1	SQLCA.Lock       = "3"

   For more information, see AutoCommit or Lock
   in the online Help.

3. Compile the script to save your changes.

   For instructions, see the User’s
   Guide
   .

Reading AutoCommit and Lock values from an external
text file

As an alternative to setting the AutoCommit and Lock properties
in a PowerBuilder application script, you can use the PowerScript ProfileString function
to read the AutoCommit and Lock values from a specified section
of an external text file, such as an application-specific initialization
file.

To read AutoCommit and Lock values from an external
text file:

1. Open the application script in which you
   want to set connection properties.

   For instructions, see the User’s
   Guide
   .

2. Use the following PowerScript syntax to specify
   the ProfileString function with the SQLCA.Lock property:

   PowerBuilder

   <b>SQLCA.Lock</b> = <b>ProfileString</b> ( <i>file</i>, <i>section</i>, <i>key</i>, <i>default</i> )

   1	<b>SQLCA.Lock</b> = <b>ProfileString</b> ( <i>file</i>, <i>section</i>, <i>key</i>, <i>default</i> )

   The AutoCommit property is a boolean, so you need to convert
   the string returned by ProfileString to a boolean.
   For example, the following statements in a PowerBuilder script read
   the AutoCommit and Lock values from the [Database] section
   of the APP.INI file:

   PowerBuilder

   string ls_string<br />ls_string=Upper(ProfileString("APP.INI","Database",<br /> "Autocommit",""))<br />if ls_string = "TRUE" then<br /> SQLCA.Autocommit = TRUE<br />else<br /> SQLCA.Autocommit = FALSE<br />end if<br />SQLCA.Lock=ProfileString("APP.INI","Database",<br /> "Lock","")

   1	string ls_string<br />ls_string=Upper(ProfileString("APP.INI","Database",<br />   "Autocommit",""))<br />if ls_string = "TRUE" then<br />   SQLCA.Autocommit = TRUE<br />else<br />   SQLCA.Autocommit = FALSE<br />end if<br />SQLCA.Lock=ProfileString("APP.INI","Database",<br />   "Lock","")

3. Compile the script to save your changes.

Getting values from theregistry

If the AutoCommit and Lock values are stored in an application
settings key in the registry, use the RegistryGet function
to obtain them. For example:

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