Sybase IQ 12.4.0 Backup and system administration, Using Isnull and Coalesce

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Using ISNULL() and COALESCE()

Adaptive Server IQ 12.4.0

 

The NUMBER(*) function is not supported and should be deleted from the

 

Adaptive Server IQ Reference Manual.

 

9.4.11 Using ISNULL() and COALESCE()

 

 

ISNULL() and COALESCE() can be used to convert NULL values into

 

something else. If these are used with an outer join, the production of this

 

expression gets pushed below the outer join. This behavior is acceptable on the

 

row-preserving side of the join, but on the side that NULLs are added to, it can

 

produce incorrect results. The ISNULL is processed in the vertical cursor, then

 

NULLs are added in the outer join.

 

9.5 Backup and system administration

 

9.5.1 New options for reserving space

 

 

Two new options let you control the amount of space reserved for adding more

 

disk space.

 

RESERVED_MAIN_DBSPACE_MB

 

Function

Controls the amount of space Adaptive Server IQ reserves for adding dbspaces

 

to the main IQ Store.

 

Allowed Values

Integer greater than zero, in megabytes

 

Default

1

 

Description

This option lets you control the amount of space Adaptive Server IQ sets aside

 

space in your main IQ Store, so that if you run out of disk space there you can

 

add a new dbspace.

 

 

Adaptive Server IQ sets aside 1 MB by default. This value is usually sufficient

 

to run the DDL commands.

 

 

You do not need to set aside room to hold the new dbspace. This option only

 

provides space for executing related DDL commands.

RESERVED_TEMP_DBSPACE_MB

 

Function

Controls the amount of space Adaptive Server IQ reserves for adding dbspaces

 

to the Temporary IQ Store.

 

Allowed Values

Integer greater than zero, in megabytes

 

34

Release Bulletin for Digital UNIX

Image 34
Contents Release Bulletin Adaptive Server IQ For Digital Unix Product summaryRequired Operating System Patches Required Operating System Patches Adaptive Server IQAdaptive Server IQ Converting 12.0.x databases to RestrictionsRelease Bulletin for Digital Unix Following outer join format is supported Setting the Ldlibrarypath Environment Variable Installation InstructionsDocumentation for this version Obtaining query plans Accessing Current Release Bulletin InformationSpecial migration instructions Go to support.sybase.comChanged functionality in this version Changed functionality in Adaptive Server IQImproved stored procedure output Adaptive Server IQ Known problems Adaptive Server IQ Stopasiq utilityAdaptive Server IQ Queries Temporary tables in proceduresData definition 1 ANY, SOME, and ALL subquery supportOutput to file in Dbisql Adaptive Server IQ OperationsLarge in subqueries Changing length of Dbisql column valuesUnsupported terminal types cause Dbisql error User-defined variable issueDbspawn Error when starting a server User-defined variable issue Adaptive Server IQAdd Service utility installed only with Server Components Problems with Add User-defined Data Type wizardDSE not installed on Windows client systems Notification message setting omitted from Index PropertiesStartup, shutdown, and connection Documentation updates and clarificationsProduct compatibilities Data Type column in Table Editor retains focusAdditions to the startasiq or asiqsrv12 command-line options Specifying server switchesUsing -v switch on 64-bit platforms Gm command line optionGn command-line option Gm command line option Adaptive Server IQConfirming connections Using Odbc connectivity with UnixAdaptive Server IQ Confirming connections Using a .odbc.ini file Adaptive Server IQ Using a .odbc.ini fileStopasiq utility Addition to Stop Database statement Adaptive Server IQ Addition to Stop Database statementError in Dbstop example Adaptive Server IQ Error in Dbstop exampleConfiguration files do not accept quotes Disconnect details omittedData definition DDL Switch must be uppercaseAdaptive Server IQ Switch must be uppercase Change to Create Database statementJoint Virtual Table JVT definition LowDisk functions as HighGroupColumn Limit Correction IQ database file paths must be uniqueError on Create Dbspace Error documenting IQ PathError in raw partition limit Adaptive Server IQ Error documenting IQ PathAddition to Drop Database statement Size clause of Create DbspaceSize clause of Create Dbspace Adaptive Server IQ Recommended index types Changes to Using join indexesAdaptive Server IQ Recommended index types Changes to Using join indexes Adaptive Server IQ Id custid idlnameAdaptive Server IQ Changes to Using join indexes Error in Diskstriping default Data manipulation DMLAdaptive Server IQ Default Support for joins between stores or databasesNew and changed general database options New and changed general database options Adaptive Server IQAdaptive Server IQ Description InsertnumberrowsperrawiobufferCorrections to Insert Location Description Adaptive Server IQNumber* function not supported String function Repeat is supportedCorrection to Char function Adaptive Server IQ String function Repeat is supportedUsing Isnull and Coalesce Adaptive Server IQ Backup and system administrationUsing Isnull and Coalesce New options for reserving spaceChange to error message Insufficient disk spaceForced recovery and leaked space recovery Effect of checkpoints Adaptive Server IQStorage within the database as in use Dbccoption option Spiqcheckdb Set dbccoption to 2, as a temporary option Improved output in stored procedures New Stored Procedure ColumnsSpiqstatus now displays IQ Page Size Minpasswordlength optionTransaction Log utility Maintaining a transaction log or mirror Setting PrefetchBufferLimit option Error message for buffer cache settingsGrant Connect for existing user ID Documentation on Data Backup and Recovery Dropping users may delete tablesChanges to Backup statement Cleaning up after abnormal exitMonitoring server activity Client applications Using PC client applicationsCreating attribute tables for PowerBuilder Help filesTechnical Support Adaptive Server IQ plug-in help reflects Multiplex supportOther sources of information Sybase Certifications on the WebTechinfo.sybase.com