CREATE DATABASE statement

Creates a new OpenEdge database.

Syntax 

 

CREATE DATABASE new-database [ FROM old-database [ NEW-INSTANCE ] ] [ REPLACE ] [ NO-ERROR ]

new-database

A CHARACTER expression that returns the absolute or relative pathname of the database you want to create. Any relative pathname is relative to the current working directory. If the database already exists, a new database is not created unless you specify REPLACE. The pathname is restricted to alphanumeric characters. Diacritical marks and the symbols \ " ’ * ; | ? [ ] ( ) ! { } < > @ + = : ~ are not permitted.

FROM old-database

A CHARACTER expression that returns the name of the database whose schema and data you want to copy to the new database. The value of old-database can be an absolute or relative pathname or one of the special strings "EMPTY", "DEMO", or "SPORTS". If you omit this option, the AVM creates an empty database. Any relative pathname is relative to the current working directory.

NEW-INSTANCE

If specified, the AVM assigns the new database a new globally unique identifier (GUID) value as the database identifier. If not specified, the AVM assigns the new database the same GUID database identifier as the old database.

When you create a new database by copying an existing database provided by OpenEdge (such as the empty database, demo database, or Sports2000 database), the AVM always assigns the new database a new GUID database identifier.

Note:

Use this option only when creating a new database by copying an existing database.

REPLACE

If specified and a database already exists with the name specified by new-database, the existing database is deleted and replaced with the new database. If not specified and a database already exists with the name specified by new-database, an error occurs.

NO-ERROR

Suppresses ABL errors or error messages that would otherwise occur and diverts them to the ERROR-STATUS system handle. If an error occurs, the action of the statement is not done and execution continues with the next statement. If the statement fails, any persistent side-effects of the statement are backed out. If the statement includes an expression that contains other executable elements, like methods, the work performed by these elements may or may not be done, depending on the order the AVM resolves the expression elements and the occurrence of the error.

To check for errors after a statement that uses the NO-ERROR option:

Check the ERROR-STATUS:ERROR attribute to see if the AVM raised the ERROR condition.

Check if the ERROR-STATUS:NUM-MESSAGES attribute is greater than zero to see if the AVM generated error messages. ABL handle methods used in a block without a CATCH end block treat errors as warnings and do not raise ERROR, do not set the ERROR-STATUS:ERROR attribute, but do add messages to the ERROR-STATUS system handle. Therefore, this test is the better test for code using handle methods without CATCH end blocks. ABL handle methods used in a block with a CATCH end block raise ERROR and add messages to the error object generated by the AVM. In this case, the AVM does not update the ERROR-STATUS system handle.

Use ERROR-STATUS:GET-MESSAGE( message-num ) to retrieve a particular message, where message-num is 1 for the first message.

If the statement does not include the NO-ERROR option, you can use a CATCH end block to handle errors raised by the statement.

Some other important usage notes on the NO-ERROR option:

NO-ERROR does not suppress errors that raise the STOP or QUIT condition.

A CATCH statement, which introduces a CATCH end block, is analogous to a NO-ERROR option in that it also suppresses errors, but it does so for an entire block of code. It is different in that the error messages are contained in a class-based error object (generated by the AVM or explicitly thrown), as opposed to the ERROR-STATUS system handle. Also, if errors raised in the block are not handled by a compatible CATCH block, ON ERROR phrase, or UNDO statement, then the error is not suppressed, but handled with the default error processing for that block type.

When a statement contains the NO-ERROR option and resides in a block with a CATCH end block, the NO-ERROR option takes precedence over the CATCH block. That is, an error raised on the statement with the NO-ERROR option will not be handled by a compatible CATCH end block. The error is redirected to the ERROR-STATUS system handle as normal.

If an error object is thrown to a statement that includes the NO-ERROR option, then the information and messages in the error object will be used to set the ERROR-STATUS system handle. This interoperability feature is important for those integrating code that uses the traditional NO-ERROR technique with the newer, structured error handling that features error objects and CATCH end blocks.

Example 

This procedure prompts for the name of a database to connect. If the database does not exist, the procedure creates it.

 

r-credb.p

DEFINE VARIABLE dbname AS CHARACTER NO-UNDO LABEL "Database" FORMAT "x(65)".   /* Prompt the user for the name of a demo database to connect. */ SET dbname HELP "Enter the name of your database."   WITH FRAME dbname-frame SIDE-LABELS.   /* If the entered name does not have the .db suffix, add it. This is necessary    for the search function to work correctly. */ IF LENGTH(dbname) < 3 THEN   dbname = dbname + ".db". ELSE IF SUBSTRING(dbname, LENGTH(dbname) - 2) = ".db" THEN   dbname = dbname + ".db".   /* If the database does not exist, create it from Sports2000. */ IF SEARCH(dbname) = ? THEN DO: MESSAGE "Database does not exist. Do you want to create it?"     VIEW-AS ALERT-BOX QUESTION BUTTONS YES-NO TITLE "Connect Database"     UPDATE create-it AS LOGICAL.   IF create-it THEN DO: CREATE DATABASE dbname FROM "Sports2000". MESSAGE "New database created:" dbname. END. ELSE UNDO, RETRY. END.   /* Connect the database. */ CONNECT VALUE(dbname) -1.

Note 

If you omit the FROM option, the AVM uses the empty database.

See also 

ALIAS function, CONNECT statement, CONNECTED function, CREATE ALIAS statement, DATASERVERS function, DBCODEPAGE function, DBCOLLATION function, DBRESTRICTIONS function, DBTYPE function, DELETE ALIAS statement, DISCONNECT statement, ERROR-STATUS system handle, FRAME-DB function, LDBNAME function, NUM-DBS function, PDBNAME function, SDBNAME function