Release Notes
BEA Liquid Data for WebLogic Version 8.1 is real-time data integration technology built on the BEA WebLogic Server. For the most up-to-date documentation on WebLogic Server, including the WebLogic Server Release Notes, see http://www.oracle.com/technology/documentation/index.html. For the latest version of these release notes, see http://download.oracle.com/docs/cd/E13190_01/liquiddata/docs81/relnotes/index.html.
Liquid Data provides on-demand access to, and aggregation of, information in relational databases, XML files, Web services, and packaged and custom applications with Application Views. It also provides the facility for pluggable custom functions through which you can access any other type of resource. Liquid Data features an easy-to-use Data View Builder for drag-and-drop design and testing of queries using XML schema representations of the data in various types of data sources.
These release notes include the following topics:
Liquid Data 8.1 SP2 is a maintenance release. It includes fixes and features, as detailed in Table 1. For details about the features in the first release Liquid Data 8.1, see Table 2.
The Liquid Data Control is now distributed and available directly from WebLogic Workshop. Previously, the Liquid Data Control was installed into Workshop as part of the Liquid Data installation process. |
Using Liquid Data Controls to Develop Workshop Applications in the Application Developer's Guide |
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You can now optionally specify the data sources for XML files and delimited files at query runtime. |
Configuring Access to Delimited Files and Configuring Access to XML Files in the Administration Guide; and xs:document in the XQuery Reference Guide |
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There are many improvements to the Data View Builder, including more efficient query generation and look-and-feel improvements. |
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Liquid Data now includes checks of the status of Liquid Data objects in the Administration Console. |
Checking the Status of Liquid Data Objects in the Administration Guide |
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There are performance improvements for many query use cases, including queries that involve views. |
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There are numerous updates to the Liquid Data documentation, including revisions to the Building Queries and Data Views and a new book entitled XQuery Reference Guide. |
Liquid Data 8.1 introduced the following features. For detailed descriptions of the features, follow the links provided.
You can now create Liquid Data Controls in WebLogic Workshop to build applications that use data from Liquid Data queries. |
Using Liquid Data Controls to Develop Workshop Applications in the Application Developer's Guide |
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You can now use delimited files as data sources to use in queries. |
Configuring Access to Delimited Files in the Administration Guide |
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You can now add simple or complex input parameters to data views. |
Configuring Stored Queries in the Administration Guide |
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There are many improvements to the Data View Builder, including mapping lines and the ability to deploy queries and views directly from the Data View Builder. |
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Liquid Data supports WebLogic Server security policies, which allow you to create security rules for objects that are dynamically evaluated at runtime. |
Security in Liquid Data in the Administration Guide |
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There are now APIs to programmatically purge entries from the query cache. |
Using the Cache Purging APIs in the Application Developer's Guide |
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You can now write vendor-specific SQL queries and use them as data sources in Liquid Data. |
Defining Stored Procedures and SQL Queries in Building Queries and Data Views |
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Query plans for ad-hoc queries are cached to enhance performance of applications using ad-hoc queries. |
Liquid Data 1.1 introduced a number of new features in Version 1.1. In addition, Liquid Data 1.1 was upgraded to support WebLogic Platform version 7.0 SP2. Release 1.1 requires that WebLogic Platform version 7.0 SP2 be installed. The previous version of Liquid Data required SP1. Other than the required upgrade the current WebLogic Platform, installation prerequisites for Liquid Data remain unchanged. For details, see Installation Prerequisites in Installing Liquid Data.
The following table briefly describes new features added in Liquid Data 1.1. For detailed descriptions of the features, follow the links provided.
You can now access stored procedures defined in relational databases without requiring the use of database adapters. |
Defining Stored Procedures in Building Queries and Data Views |
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You can now define user-defined complex parameter types which take an XML data stream as an input. |
Using Complex Parameter Types in Queries in Building Queries and Data Views |
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You can now add simple or complex input parameters to data views. |
Using Data Views as Data Sources in Building Queries and Data Views |
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Multiple levels of data views over data views is fully supported. |
You can now create as many levels of data views as you need. (Previously only one layer of abstraction was possible.) |
Using Data Views as Data Sources in Building Queries and Data Views |
Liquid Data now supports XML Namespace declarations in queries and schema. |
Understanding XML Namespaces in Building Queries and Data Views |
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There are now |
Invoking Queries in JSP Clients in the Application Developer's Guide |
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There is now enhanced support of editing target schemas in the Data View Builder. For example, you can specify the data type and namespace of attributes and elements. |
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Liquid Data supports multi-byte data from the underlying data sources. |
Internationalization Support in the Installation Guide |
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You can now configure domains with Liquid Data and other BEA products directly through the WebLogic Domain Configuration Wizard. |
Deployment Tasks in the Liquid Data Deployment Guide |
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Supported Databases and Drivers in the WebLogic Platform documentation. |
Release 1.0.1 of Liquid Data featured enhanced platform support.
The following information was added to the product documentation for Release 1.0.1:
The BEA Dev2Dev web site contains developer tools, code samples, and other useful information for developers using Liquid Data. Visit the Liquid Data Dev2Dev site at the following location:
http://dev2dev.bea.com/products/liquiddata81
There are also newsgroups available from browsing and posting at the following location:
http://newsgroups.bea.com/
The process cannot access the file because it is already being used by another process
Ctl-C
command to shut down the Liquid Data server. Doing so could corrupt the Liquid Data
configuration files in the server domains (config.xml
).Instead, make sure that you always shut down the server through the WebLogic Server Administration Console. For example, the WLS Administration Console using the default port is at the following URL for a local server:
http://localhost:7001/console
Instructions on how to shut down the Liquid Data server from the Administration Console are provided in Starting and Stopping the Server in the Liquid Data Administration Guide.
For complete information on how to recover a corrupted configuration file, see "Backing Up Configuration Data" in the topic Recovering Failed Servers in the WebLogic Server system administration documentation.
This section describes limitations in the current BEA Liquid Data for WebLogic 8.1 release and includes possible workarounds, where applicable.
The table below lists a CR (Change Request) number for each problem. Refer to this number to track the solution as the problems are resolved.
Please contact BEA customer support at http://support.bea.com for assistance in tracking any unresolved problems.
Use of |
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When you use the |
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This is a known Java Virtual Machine (JVM) bug from Sun Microsystems, Inc. (logged as ID: 4414844). As a workaround, add one hour to the time of day value when you build the query. |
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The |
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The |
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For large numbers (larger than 2147483647 and smaller than -2147483647), do not use |
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If you are using a NIS/NFS based file system and have Liquid Data installed on multiple systems, each time you run the installer it will rewrite the |
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All platforms when using NIS/NFS-based file system with Liquid Data installed on multiple systems. |
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Edit the |
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Removing a generated Web Service from the Liquid Data web_services_gen directory does not automatically remove it from the WebLogic Server (WLS) Web Services table as expected. |
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When a generated Web Service is removed from the |
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Follow these steps to remove a generated Web Service for a stored query in Liquid Data: 1. Use Administration Console to browse the 2. Click the trash can icon (Delete) next to the EAR file for the generated Web Service that you intend to remove and confirm. |
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The Monitor tab in the Liquid Data Administration Console does not appear in a clustered configuration. |
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When Liquid Data is deployed in a cluster, the statistical data in the Liquid Data > Monitor tab disappears from Liquid Data console. |
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Unsupported JDBC type found when running an existing query on Oracle RDBMS. |
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When using the Oracle 9.2 JDBC driver with Oracle 8.1.7, some queries might fail with unsupported JDBC data type errors. |
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If you are using Oracle 8.1.7, use the Oracle 8.1.7 JDBC driver; if you are using Oracle 9i, use the Oracle 9.2 JDBC driver. For details on changing the JDBC driver, see http://download.oracle.com/docs/cd/E13222_01/wls/docs81/jdbc/thirdparty.html#1043614 |
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Changes to Liquid Data configuration may adversely affect the ability of WebLogic Server to restart after a server failure. |
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The Liquid Data environment should be frequently exported. This is especially true when configuration changes are made such as adding, removing, or updating a data source. Using a recently exported configuration, the workaround for the problem described above is to:
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In IBM DB2, when returning a result set from a stored procedure, connections are not being released. |
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When using the IBM DB2 Type 3 JDBC driver to access stored procedures, connections are not always released, which can cause subsequent queries to fail. This is a problem in the DB2 Type 3 JDBC driver. |
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Use the IBM DB2 Type 2 JDBC driver; the Type 2 driver does not have this problem, and releases the connections as expected. |
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Undeploying/Deploying the LDS.ear file sometimes requires the user to log back into WLS to gain access to the Liquid Data Administration Console. |
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If you undeploy the LDS.ear application from the WebLogic console, when you redeploy the application, you might need to log back into the console in a new session in order to see the Liquid Data Administration Console node in the WebLogic console. |
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Start a new console session by exiting your browser and logging into the Liquid Data Administration Console again. |
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Cannot project an element that is not mapped in the underlying view. |
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When you create a data view in Liquid Data, you must map all elements and/or attributes to the target schema. That is, every element in the target schema must have a valid mapping. If you do not map all of the elements and attributes, queries against the resulting view might fail. |
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Map all elements and attributes to the target schema (even if they are optional) when creating data views. |
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Liquid Data console hangs if you are using the Sun 1.4.1_01 Java plugin in your browser. |
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If you are using the Sun 1.4.1_01 Java plugin in your Internet Explorer or Netscape browser, accessing the Liquid Data console will hang your browser and might hang the machine in which the browser runs. |
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Do not use the Sun 1.4.1_01 JVM; upgrade to the Sun 1.4.1_02 or later JVM from java.sun.com. |
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If NVARCHAR2 Oracle Column is passed to Function eq() and "Query Parameter", SQLException will occur. |
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Using Oracle 8.1.7 with the 8.1.7 JDBC driver, if you pass an |
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If you encounter this problem, use one of the Oracle 9i JDBC drivers. |
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Japanese filenames do not display in the repository Administration Console. |
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If files are stored in the Liquid Data repository with Japanese filenames, they cannot be configured correctly with the Liquid Data Administration Console. |
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Do not use Japanese characters in your repository directory or file names. |
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Cannot process |
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When mapping numeric constants to the stored procedure inputs that contain input parameters of type |
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When you map any constants to input parameters of type |
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Due to a problem in the Informix JDBC driver, when executing a stored procedure against an Informix data source, the query can hang without returning any results. |
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When using stored procedures with Informix data sources, set the Prepared Statement Cache Size to 0 in the JDBC Connection Pool used in the data source. The Informix JDBC driver does not behave properly when using stored procedures with a cache size greater than zero. This will not impact the performance of the stored procedure because Stored Procedure statements are not cached. BEA recommends creating two different JDBC connection pools for Informix data sources, one for stored procedures and another for Table access. Set the Prepared Statement Cache Size property to a non-zero value for the Table access JDBC pool and set it to zero for the Stored Procedure access JDBC pool. |
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You cannot select The release notes from the Oracle Patch Set 92021 has the following description of this problem: JDBC Nulls are being padded instead of blanks when selecting a |
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If you are using Oracle 9i with |
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If you try to enter a name for the Liquid Data repository that contains Japanese characters (from the Administration Console —> Liquid Data —> Configuration tab —> General tab —> Repository Directory), a configuration error occurs. |
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Do not use Japanese character in your repository directory name. |
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Liquid Data does not handle the target namespace defined in the WSDL properly, resulting in overloading problems. |
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When using multiple web services as data sources, it is possible to have namespace collisions where Liquid Data cannot differentiate between the two web services. |
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When designing WebLogic Workshop web services, you may need to alter the |
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Liquid Data RDBMS Data Source against Oracle 7.3.4 fails with Oracle 9 JDBC Drivers |
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If you use one of the Oracle 9 JDBC drivers to access an Oracle 7.3.4 database and you create a Liquid Data Data Source that accesses that JDBC data source, the data source initialization fails. |
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If you are using Oracle 7.3.4, use the Oracle 8.1.7 JDBC driver instead of one of the Oracle 9 JDBC drivers/ |
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Certain combinations of Oracle JDBC drivers and servers incorrectly report the type of DATE columns as DATETIME, therefore Liquid Data treats them as DATETIME. |
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If you encounter this problem, add a |
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License manager not always using the newest license for Liquid Data. |
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If you have multiple Liquid Data licenses in the |
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Whenever you update the Liquid Data license in the |
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Cannot create elementFormDefault="qualified" attribute in the Data View Builder. |
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You cannot create schemas with the |
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If you need to use schemas with the |
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Schema URLs for import and include statements must resolve or web service generation will fail. |
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If you are generating a web service with Liquid Data, any import and include statements in the schema file for the stored query must have a URL that can be resolved by the WSDL parser. Local filenames or relative URLs will not resolve in the generated web service. |
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Do not use local filenames in import/include statements for target schemas. Make all import and include statements in a target schema resolvable over http, ftp, or some other network protocol available to the web service. |
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If the IP address changes while the Liquid Data server is running on the local machine, connecting to some data sources with the Data View Builder fails. |
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If you are running Data View Builder and the Liquid Data server locally on the same machine and if your IP address changes (for example, if you start up Liquid Data and the Data View Builder on a laptop connected to one network, then put the laptop in sleep mode and reconnect it to another network), you might not be able to use the Data View Builder to access certain data sources, and the Data View Builder will fail with the following error:
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If you encounter this situation, restart the Liquid Data domain and reconnect with the Data View Builder. |
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Package contains no type of this name error after changing the query many methods access in an existing JCX file. |
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If you edit several methods in rapid succession in an existing Liquid Data Control ( |
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If you encounter this problem, save your work, restart WebLogic Workshop, and update the Liquid Data Control as described in Updating an Existing Liquid Data Control if Schemas Change in the Liquid Data Application Developer's Guide. |
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NetUI does not generate the input form correctly for queries with input parameters of |
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If you use WebLogic Workshop NetUI to generate a page flow JPF file from a Liquid Data control and include queries with input parameters having types |
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In the JSP file with the input form(s), the inputs with these types include a message similar to the following:
You can treat these types of input parameters as strings. To work around this, substitute code similar to the following for the data cell corresponding to the input parameter:
where |
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In Data View Builder, projects that contain Web Service complex mappings from web services returning arrays might return element names different from the target schema. |
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Web Services returning arrays do not provide information about the name of each element in the arrays returned. While this is valid in WSDL, it is not supported by XML Schema. To overcome this limitation, Data View Builder assigns the name "item" to all such not-named elements. If you map (copy & paste with map) such an array from the output of the web service to the target schema, Data View Builder carries over the name "item" to the expanded target schema. However, the web service, when called, returns elements most likely not named "item". This means that the result of the query would not match the target schema. This can be an issue when you deploy the query or view and specify a target schema. |
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If you run into this issue, edit the target schema so that the element names match those returned by the web service. Note that you must modify the target schema outside of the Data View Builder project, because you cannot modify the name of a mapped element in Data View Builder. Use the edited target schema for deploying the query and/or view, but not in the Data View Builder project. |
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Inconsistent source schema view using different DB2 JDBC drivers. |
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The data direct DB2 JDBC driver returns a different schema from the IBM type2 driver for DB2 7.2. The data direct driver returns the schema and catalog name; the IBM driver does not. |
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If you have built queries using the IBM DB2 JDBC 7.2 driver and now want to use new BEA JDBC driver. you must specify a unique schema name and catalog name in the Liquid Data data source configuration. Then the queries will run as before. |
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Sybase and Microsoft stored procedures do not work with Liquid Data when using the BEA Sybase JDBC driver. |
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The BEA JDBC drivers for Sybase and Microsoft SQL Server do not properly transform the stored procedure name needed by the Liquid Data server. This causes errors similar to the following to occur:
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If you are accessing stored procedures in Sybase or Microsoft SQL server databases, use the JDBC drivers supplied by the vendor instead of the BEA JDBC drivers for those databases. |
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Server does not support concurrent access to PointBase databases. |
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If the Shared Connection attribute is set for a Liquid Data data source that accesses a PointBase database, concurrent queries will fail with an internal error. |
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Do not set the Shared Connection attribute for Liquid Data relational data sources that access PointBase databases. Make sure the Shared Connection box is not checked in the Configure a Relational Database Data Source Description page of the Liquid Data Administration Console for data sources accessing PointBase databases. |
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Sybase JConnect 5.5 JDBC driver returns incorrect results for "output" parameters of DECIMAL data type. |
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The Sybase JConnect 5.5 driver does not return the proper output value for stored procedures "output" parameters of DECIMAL type. |
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Use the BEA Sybase JDBC drivers for these types of stored procedures or use the Sybase JConnect 4.5 driver. |
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A query must not return a NULL value (it must return at least an empty root element) for web services generated from a Liquid Data Control where the query returns no results. |
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If you generate a Web Service from a Liquid Data Control in WebLogic Workshop, and the control accesses a query that returns no results (returns a NULL value), WebLogic Workshop throws a runtime exception because it encounters a NULL value. The exception is similar to the following:
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If you encounter this problem, modify the query so that, in the case that there are no results from the query, it still returns an empty root element (not a NULL value). For example, begin the query with the XML markup for opening the root element (for example, |
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Sample domain does not start after installing Liquid Data over an existing Liquid Data installation. |
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If you install Liquid Data over an existing Liquid Data installation (without first uninstalling the old installation), the Liquid Data sample domain will not start unless you delete the following file:
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Do not install Liquid Data over an existing Liquid Data installation without first uninstalling the old installation. If you encounter this problem, however, you can work around it by deleting the following file from the Liquid Data sample domain:
where weblogic_home is the directory in which the WebLogic platform is installed (for example, After deleting this file, you can then start the Liquid Data sample domain. |
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A query will return incorrect results if it calls a DataView that returns an empty (null) document. |
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It is possible to create a data view in the Data View Builder that will return an empty document (as opposed to an empty root element). However, results returned froma query that invokes a Data View returning an empty document will not be correct. |
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If you encounter this problem, modify the stored query which is the basis of the data view so that it will return an empty root element (in other words, it will not return a null value) even in the case that there are no results from the query. For example, begin the query with the XML markup for opening the root element (for example, |
Documentation for this product is available on an Online Documentation CD-ROM that ships with the product, and is also available on the Web at the BEA edocs documentation site at the following location:
http://download.oracle.com/docs/cd/E13190_01/liquiddata/docs81/index.html
To access the PDFs on either platform, open the Liquid Data documentation Home page in a Web browser as described above, click the PDF files button, and select the document that you want to view or print. Alternatively, from within an HTML document, click the View as PDF link on the top navigation bar to open a PDF version of the currently displayed document.
If you do not have the Adobe Acrobat Reader, you can get it for free from the Adobe Web site at http://www.adobe.com/.