1.1
Table Of Contents
- Contents
- About the SQLFire User's Guide
- Supported Configurations and System Requirements
- Getting Started with vFabric SQLFire
- Managing Your Data in vFabric SQLFire
- Designing vFabric SQLFire Databases
- Using Server Groups to Manage Data
- Partitioning Tables
- Replicating Tables
- Estimating Memory Requirements
- Using Disk Stores to Persist Data
- Exporting and Importing Data with vFabric SQLFire
- Using Table Functions to Import Data as a SQLFire Tables
- Developing Applications with SQLFire
- Starting SQLFire Servers with the FabricServer Interface
- Developing Java Clients and Peers
- Configuring SQLFire as a JDBC Datasource
- Storing and Loading JAR Files in SQLFire
- Developing ADO.NET Client Applications
- About the ADO.NET Driver
- ADO.NET Driver Classes
- Installing and Using the ADO.NET driver
- Connecting to SQLFire with the ADO.NET Driver
- Managing Connections
- Executing SQL Commands
- Working with Result Sets
- Storing a Table
- Storing Multiple Tables
- Specifying Command Parameters with SQLFParameter
- Updating Row Data
- Adding Rows to a Table
- Managing SQLFire Transactions
- Performing Batch Updates
- Generic Coding with the SQLFire ADO.NET Driver
- Using SQLFire.NET Designer
- Understanding the Data Consistency Model
- Using Distributed Transactions in Your Applications
- Using Data-Aware Stored Procedures
- Using the Procedure Provider API
- Using the Custom Result Processor API
- Programming User-Defined Types
- Using Result Sets and Cursors
- Caching Data with vFabric SQLFire
- Deploying vFabric SQLFire
- SQLFire Deployment Models
- Steps to Plan and Configure a Deployment
- Configuring Discovery Mechanisms
- Starting and Configuring SQLFire Servers
- Configuring Multi-site (WAN) Deployments
- Configuring Authentication and Authorization
- Configuring User Authentication
- User Names in Authentication and Authorization
- Configuring User Authorization
- Configuring Network Encryption and Authentication with SSL/TLS
- Managing and Monitoring vFabric SQLFire
- Configuring and Using SQLFire Log Files
- Querying SQLFire System Tables and Indexes
- Evaluating Query Plans and Query Statistics
- Overriding Optimizer Choices
- Evaluating System and Application Performance
- Using Java Management Extensions (JMX)
- Best Practices for Tuning Performance
- Detecting and Handling Network Segmentation ("Split Brain")
- vFabric SQLFire Reference
- Configuration Properties
- JDBC API
- Mapping java.sql.Types to SQL Types
- java.sql.BatchUpdateException Class
- java.sql.Connection Interface
- java.sql.DatabaseMetaData Interface
- java.sql.Driver Interface
- java.sql.DriverManager.getConnection Method
- java.sql.PreparedStatement Interface
- java.sql.ResultSet Interface
- java.sql.SavePoint Class
- java.sql.SQLException Class
- java.sql.Statement Class
- javax.sql.XADataSource
- sqlf Launcher Commands
- sqlf backup
- sqlf compact-all-disk-stores
- sqlf compact-disk-store
- sqlf encrypt-password
- sqlf install-jar
- sqlf list-missing-disk-stores
- sqlf locator
- sqlf Logging Support
- sqlf merge-logs
- sqlf remove-jar
- sqlf replace-jar
- sqlf revoke-missing-disk-store
- sqlf server
- sqlf show-disk-store-metadata
- sqlf shut-down-all
- sqlf stats
- sqlf upgrade-disk-store
- sqlf validate-disk-store
- sqlf version
- sqlf write-data-dtd-to-file
- sqlf write-data-to-db
- sqlf write-data-to-xml
- sqlf write-schema-to-db
- sqlf write-schema-to-sql
- sqlf write-schema-to-xml
- sqlf Interactive Commands
- absolute
- after last
- async
- autocommit
- before first
- close
- commit
- connect
- connect client
- connect peer
- describe
- disconnect
- driver
- elapsedtime
- execute
- exit
- first
- get scroll insensitive cursor
- GetCurrentRowNumber
- help
- last
- LocalizedDisplay
- MaximumDisplayWidth
- next
- prepare
- previous
- protocol
- relative
- remove
- rollback
- run
- set connection
- show
- wait for
- SQLFire API
- SQL Language Reference
- Keywords and Identifiers
- SQL Statements
- ALTER TABLE
- CALL
- CREATE Statements
- DECLARE GLOBAL TEMPORARY TABLE
- DELETE
- EXPLAIN
- DROP statements
- GRANT
- INSERT
- REVOKE
- SELECT
- SET ISOLATION
- SET SCHEMA
- TRUNCATE TABLE
- UPDATE
- SQL Queries
- SQL Clauses
- SQL Expressions
- JOIN Operations
- Built-in Functions
- Standard Built-in Functions
- Aggregates (set functions)
- ABS or ABSVAL function
- ACOS function
- ASIN function
- ATAN function
- ATAN2 function
- AVG function
- BIGINT function
- CASE expressions
- CAST function
- CEIL or CEILING function
- CHAR function
- COALESCE function
- Concatenation operator
- COS function
- COSH function
- COT function
- COUNT function
- COUNT(*) function
- CURRENT DATE function
- CURRENT_DATE function
- CURRENT ISOLATION function
- CURRENT_ROLE function
- CURRENT SCHEMA function
- CURRENT TIME function
- CURRENT_TIME function
- CURRENT TIMESTAMP function
- CURRENT_TIMESTAMP function
- CURRENT_USER function
- DATE function
- DAY function
- DEGREES function
- DOUBLE function
- EXP function
- FLOOR function
- HOUR function
- INTEGER function
- LCASE or LOWER function
- LENGTH function
- LN or LOG function
- LOG10 function
- LOCATE function
- LTRIM function
- MAX function
- MIN function
- MINUTE function
- MOD function
- MONTH function
- NULLIF expressions
- PI function
- RADIANS function
- RANDOM function
- RAND function
- RTRIM function
- SECOND function
- SESSION_USER function
- SIGN function
- SIN function
- SINH function
- SMALLINT function
- SQRT function
- SUBSTR function
- SUM function
- TAN function
- TANH function
- TIME function
- TIMESTAMP function
- TRIM function
- UCASE or UPPER function
- USER function
- VARCHAR function
- XMLEXISTS operator
- XMLPARSE operator
- XMLQUERY operator
- XMLSERIALIZE operator
- YEAR function
- SQLFire Built-in Functions
- Standard Built-in Functions
- Built-in System Procedures
- Standard Built-in Procedures
- SYSCS_UTIL.EMPTY_STATEMENT_CACHE
- SYSCS_UTIL.EXPORT_QUERY
- SYSCS_UTIL.EXPORT_TABLE
- SYSCS_UTIL.IMPORT_DATA
- SYSCS_UTIL.IMPORT_DATA_EX
- SYSCS_UTIL.IMPORT_DATA_LOBS_FROM_EXTFILE system procedure
- SYSCS_UTIL.IMPORT_TABLE
- SYSCS_UTIL.IMPORT_TABLE_EX
- SYSCS_UTIL.IMPORT_TABLE_LOBS_FROM_EXTFILE
- SYSCS_UTIL.SET_EXPLAIN_CONNECTION
- SYSCS_UTIL.SET_STATISTICS_TIMING
- JAR Installation Procedures
- Callback Configuration Procedures
- Heap Eviction Configuration Procedures
- WAN Configuration Procedures
- Standard Built-in Procedures
- Data Types
- SQL Standards Conformance
- System Tables
- ASYNCEVENTLISTENERS
- GATEWAYRECEIVERS
- GATEWAYSENDERS
- INDEXES
- JARS
- MEMBERS
- MEMORYANALYTICS
- STATEMENTPLANS
- SYSALIASES
- SYSCHECKS
- SYSCOLPERMS
- SYSCOLUMNS
- SYSCONGLOMERATES
- SYSCONSTRAINTS
- SYSDEPENDS
- SYSDISKSTORES
- SYSFILES
- SYSFOREIGNKEYS
- SYSKEYS
- SYSROLES
- SYSROUTINEPERMS
- SYSSCHEMAS
- SYSSTATEMENTS
- SYSSTATISTICS
- SYSTABLEPERMS
- SYSTABLES
- SYSTRIGGERS
- SYSVIEWS
- Exception Messages and SQL States
- ADO.NET Driver Reference
- SQLFire Data Types in ADO.NET
- VMware.Data.SQLFire.BatchUpdateException
- VMWare.Data.SQLFire.SQLFClientConnection
- VMware.Data.SQLFire.SQLFCommand
- VMware.Data.SQLFire.SQLFCommandBuilder
- VMware.Data.SQLFire.SQLFType
- VMware.Data.SQLFire.SQLFDataAdapter
- VMware.Data.SQLFire.SQLFDataReader
- VMware.Data.SQLFire.SQLFException
- VMware.Data.SQLFire.SQLFParameter
- VMware.Data.SQLFire.SQLFParameterCollection
- VMware.Data.SQLFire.SQLFTransaction
- vFabric SQLFire Limitations
- Troubleshooting Common Problems
- vFabric SQLFire Glossary
- Index
XMLEXISTS operator
XMLEXISTS is an SQL/XML operator that you can use to query XML values in SQL.
The XMLEXISTS operator has two arguments, an XML query expression and a SQLFire XML value.
Syntax
XMLEXISTS ( xquery-string-literal
PASSING BY REF xml-value-expression [ BY REF ] )
Must be specified as a string literal. If this argument is specified as a parameter,
an expression that is not a literal, or a literal that is not a string (for example an
xquery-string-literal
integer), SQLFire throws an error. The xquery-string-literal argument
must also be an XPath expression that is supported by Apache Xalan. SQLFire
uses Apache Xalan to evaluate all XML query expressions. Because Xalan does
not support full XQuery, neither does SQLFire. If Xalan is unable to compile
or execute the query argument, SQLFire catches the error that is thrown by
Xalan and throws the error as a SQLException. For more on XPath and XQuery
expressions, see these Web sites: http://www.w3.org/TR/xpath and
http://www.w3.org/TR/xquery/.
Must be an XML data value and must constitute a well-formed SQL/XML
document. The xml-value-expression argument cannot be a parameter.
xml-value-expression
SQLFire does not perform implicit parsing nor casting of XML values, so use
of strings or any other data type results in an error. If the argument is a sequence
that is returned by the SQLFire XMLQUERY operator on page 576, the argument
is accepted if it is a sequence of exactly one node that is a document node.
Otherwise SQLFire throws an error.
Optional keywords that describe the only value passing mechanism supported
by SQLFire. Since BY REF is also the default passing mechanism, the
BY REF
XMLEXISTS operator behaves the same whether the keywords are present or
not. For more information on passing mechanisms, see the SQL/XML
specification.
Operator results and combining with other operators
The result of the XMLEXISTS operator is a SQL boolean value that is based on the results from evaluating the
xquery-string-literal against the xml-value-expression. The XMLEXISTS operator returns:
When the xml-value-expression is null.
UNKNOWN
When the evaluation of the specified query expression against the specified xml-value
returns a non-empty sequence of nodes or values.
TRUE
When evaluation of the specified query expression against the specified xml-value
returns an empty sequence.
FALSE
The XMLEXISTS operator does not return the actual results from the evaluation of the query. You must use the
XMLQUERY operator to retrieve the actual results.
Since the result of the XMLEXISTS operator is an SQL boolean data type, you can use the XMLEXISTS operator
wherever a boolean function is allowed. For example, you can use the XMLEXISTS operator as a check constraint
in a table declaration or as a predicate in a WHERE clause.
vFabric SQLFire User's Guide574
vFabric SQLFire Reference