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Note:
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OpenEdge identifies all connected databases for access within an external procedure or class at the start of execution for each compilation unit. Therefore, you cannot directly connect a database using this statement and directly access tables in the database from within the same external procedure or class. Instead, you can directly connect the database in one procedure or class, and from this one call another external subprocedure, or instantiate another class, that accesses the database tables.
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CONNECT
{
{ physical-name | VALUE ( expression ) } [ options ] | options
}
[ NO-ERROR ]
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A character expression (a quoted string, field name, variable name, or similar expression) whose value starts with the Physical Database Name (
-db) connection parameter followed by zero or more of the same client connection parameters that you can specify in
options.
One or more client connection parameters (unquoted), similar to those used to start OpenEdge. Valid options are a subset of OpenEdge startup parameters that include all client database connection parameters. If you specify
options without
physical-name or
VALUE (expression), the first database connection parameter must be the Physical Database Name (
-db) parameter. The specification of the User ID (
-U) parameter (and Password (
-P) parameter, if required), determines the user identity for the connection, and its tenancy (if the database is multi-tenant). Note that these (and all connection) parameters are case sensitive.
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Caution:
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If you do not specify -U and -P, for backward compatibility, OpenEdge attempts to connect the database with a default connection identity. This default connection identity can be set using either the blank ( "") user ID or the user ID of the operating system process in which the AVM is running. The user ID set for the default connection identity depends on the domain configuration in the database. For more information on connecting with a default identity, see the User ID ( -U) parameter description in OpenEdge Deployment: Startup Command and Parameter Reference. For more information on the effects of connecting a database with a default identity, see the Notes of this statement entry.
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For more information on all database client connection parameters, see
OpenEdge Deployment: Startup Command and Parameter Reference.
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.
For the CONNECT statement with NO-ERROR, the option does not suppress all errors produced by the server; only errors caused by the CONNECT statement itself. For example, if the server to which you are connecting runs out of resources, its error message will not be suppressed. If a CONNECT error occurs (for example, the database does not exist or is in use in single‑user mode), error information is written to the ERROR-STATUS system handle.
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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.
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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.
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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.
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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.
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CONNECT C:\OpenEdge\WRK\db\Sports2000 -H dbserver -S 1900 NO-ERROR.
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CONNECT -db C:\OpenEdge\WRK\db\Sports2000 -H dbserver -S 1900 NO-ERROR.
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CONNECT VALUE("-db C:\OpenEdge\WRK\db\Sports2000 -H dbserver -S 1900")
NO-ERROR.
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CONNECT VALUE("-db C:\OpenEdge\WRK\db\Sports2000 -H dbserver") -S 1900
NO-ERROR.
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In the next example, assume database sports2000 has not been previously connected, so the following
r-cnct1.p procedure fails. At the start of execution,
r-cnct1.p checks whether
sports2000 is connected. If
sports2000 is not connected, a run‑time error occurs. As shown in the example, attempting to connect to
sports2000 within the procedure does not solve the problem:
Instead, split r-cnct1.p into two procedures, as shown in
r-dispcu.p and
r-cnct2.p:
This time, database sports2000 is connected before
r-dispcu.p is invoked, so
r-dispcu.p runs successfully.
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To authenticate the user identity specified for a database connection:
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The user’s security domain must be defined in the OpenEdge database.
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The user authentication operation of the CONNECT statement can fail for any one of the following reasons, among others:
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The User ID (-U) connection parameter includes an invalid format.
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For the connection identity set with the CONNECT statement, OpenEdge creates a sealed security token containing the user credentials for the database connection, which you can return as a client-principal object using the GET-DB-CLIENT function. This client-principal is created even if OpenEdge connects the database with a default connection identity (that is, you do not specify -U and -P). However, for a default connection identity, OpenEdge does not seal the client-principal using the access code configured for a registered domain. Instead, OpenEdge creates a unique internal access code to seal the object. As a result, you cannot use the sealed client-principal object to assign the default user identity it represents to any OpenEdge database connection or ABL session.
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Each connected database is assigned a logical name for the current session, and is referred to by this logical name during the session. Use the Logical Database Name ( -ld) parameter to specify a logical name. If the logical name is not specified using the -ld parameter, then the physical database filename, without the .db suffix, is the default logical name. For example, if the physical name is /users/eastcoast/proapp/mydb.db, then the default logical name is mydb. Logical names are not case sensitive.
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Databases can have aliases (see also ALIAS function). A database can have more than one alias, but each alias refers to only one database. The first database connected during a given session automatically receives the alias DICTDB. The first database connected that has a _menu file automatically receives the alias FTDB. You can reassign the FTDB alias to any other FAST TRACK database.
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If you run a procedure that requires a database and that database is not connected, the AVM searches for the database in the auto‑connect lists in all connected databases. If the AVM finds the required database there, it automatically attempts to connect to the database with the parameters set for it in the auto‑connect list. You can edit the auto‑connect list using the database utilities in the OpenEdge Data Dictionary. If the AVM does not find it, the connection attempt fails.
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Connection information found in an OpenEdge auto‑connect list is merged with connection information in a CONNECT statement that connects the database. So, if you connect a database with a CONNECT statement, and that database already has an entry in the OpenEdge auto‑connect list of a connected database, the connection information in the auto‑connect list and the CONNECT statement is merged. However, the connection information in the CONNECT statement takes precedence.
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The ABL client executable might require use of a privileged account that allows it to open raw disk devices or large databases. Thus, you can open any databases specified on the startup command line with raw I/O. Note that after startup on Unix, the client executable relinquishes the privileges that allow it to open raw disk devices. As a result, you cannot use the CONNECT statement to establish a raw I/O connection to a database in single‑user or multi‑user direct‑access mode.
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If you want to run a multi‑user direct‑access session in non‑raw mode, you must start the database server with the Buffered I/O ( -r) parameter.
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If a database and accompanying before‑image file have read‑only permissions ( r--r--r--) and you try to connect to that database in single‑user or multi‑user mode using the CONNECT statement, the connection will fail with the following error:
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ALIAS function,
CONNECTED function,
CREATE ALIAS statement,
CREATE CALL statement,
DATASERVERS function,
DBCODEPAGE function,
DBCOLLATION function,
DBRESTRICTIONS function,
DBTYPE function,
DBVERSION function,
DELETE ALIAS statement,
DISCONNECT statement,
FRAME-DB function,
LDBNAME function,
NUM-DBS function,
PDBNAME function,
SDBNAME function,
SET-DB-CLIENT function,
SETUSERID function
