BorlandTalk.com Borland discussion newsgroups   Archives   FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in to check your private messages   Log in  'How to know whether the table has been locked.          BorlandTalk.com Forum Index -> Delphi Databases (SQL Servers) View previous topic :: View next topic   Author Message Simon Yeung Guest Posted: Mon Jul 26, 2004 3:47 am    Post subject: 'How to know whether the table has been locked. I want to lock a table when someone access it, at this time, another user cannot access the table. please tell me which command or method that can let me know the state (locked or unlock) of table. Thx Back to top Dmitry Arefiev [gs-soft.r Guest Posted: Mon Jul 26, 2004 6:01 am    Post subject: Re: 'How to know whether the table has been locked. Hi Simon ! To answer with technical details i should know your RDBMS. 1) In general, most simple method will be to try lock a table. If trial has been failed - table is locked (most probably). 2) Some RDBMS have API's returning extensive info and statistic about own state. For example, Oracle has dynamic views, including v$lock. It returns a list of all locks in instance. 3) What for at all you need to lock full table ? May be some subset of rows will be enough ? Try define precise subset and keep it locked for minimal time ... Regards, Dmitry -- Dmitry Arefiev, gs-soft Company, community.gs-soft.com Personal - www.da-soft.com SAPx - Delphi to SAP R/3 direct access Saphir - SAP R/3 metadata on your fingertips MetaBase - ERWIN model in Delphi applications NCOCI8 - Freeware Delphi to ORACLE direct access Simon Yeung wrote: Quote: I want to lock a table when someone access it, at this time, another user cannot access the table. please tell me which command or method that can let me know the state (locked or unlock) of table. Thx Back to top Simon Yeung Guest Posted: Mon Jul 26, 2004 6:43 am    Post subject: Re: 'How to know whether the table has been locked. First, thank for your reply, and then sorry for missing some information. I am using Microsoft SQL DB, development tool is delphi. thank for your suggestion. I am using your first method now, although it is work, i want to know whether have method to know the state of table. so i need not to waiting for "time-out" message if the table is locked. Thx for your attention "Dmitry Arefiev [gs-soft.ru]" <darefiev (AT) gs-soft (DOT) ru> ¦b¶l¥ó news:41049d51 (AT) newsgroups (DOT) borland.com ¤¤¼¶¼g... Quote: Hi Simon ! To answer with technical details i should know your RDBMS. 1) In general, most simple method will be to try lock a table. If trial has been failed - table is locked (most probably). 2) Some RDBMS have API's returning extensive info and statistic about own state. For example, Oracle has dynamic views, including v$lock. It returns a list of all locks in instance. 3) What for at all you need to lock full table ? May be some subset of rows will be enough ? Try define precise subset and keep it locked for minimal time ... Regards, Dmitry -- Dmitry Arefiev, gs-soft Company, community.gs-soft.com Personal - www.da-soft.com SAPx - Delphi to SAP R/3 direct access Saphir - SAP R/3 metadata on your fingertips MetaBase - ERWIN model in Delphi applications NCOCI8 - Freeware Delphi to ORACLE direct access Simon Yeung wrote: I want to lock a table when someone access it, at this time, another user cannot access the table. please tell me which command or method that can let me know the state (locked or unlock) of table. Thx Back to top Dmitry Arefiev [gs-soft.r Guest Posted: Mon Jul 26, 2004 1:05 pm    Post subject: Re: 'How to know whether the table has been locked. Hi Simon ! 1) To avoid waiting time-out use following batch query: SET LOCK_TIMEOUT 0; SELECT * FROM MyTab WITH(ROWLOCK,UPDLOCK) WHERE ... And see MSSQL docu, chapter "Locking Hints", for details about content of WITH clause. TABLOCK may be interesting for you. 2) See SP_LOCK system procedure. It returns info about current locks in system. Regards, Dmitry -- Dmitry L. Arefiev, gs-soft Company, http://www.gs-soft.com Personal - http://www.da-soft.com SAPx - Delphi to SAP R/3 direct access Saphir - SAP R/3 metadata on your fingertips MetaBase - ERWIN model in Delphi applications GISx - GIS system booster and simplifier NCOCI8 - Freeware Delphi to ORACLE direct access SCard - Complete PKCS11 and X509 solution Back to top Simon Yeung Guest Posted: Tue Jul 27, 2004 2:05 am    Post subject: Re: 'How to know whether the table has been locked. Dear Dmitry: Thx so much, I don't know that I can set lock timeout, it is very useful command. Regards, Simon "Dmitry Arefiev [gs-soft.ru]" <darefiev (AT) da-soft (DOT) com> ¦b¶l¥ó news:41050047 (AT) newsgroups (DOT) borland.com ¤¤¼¶¼g... Quote: Hi Simon ! 1) To avoid waiting time-out use following batch query: SET LOCK_TIMEOUT 0; SELECT * FROM MyTab WITH(ROWLOCK,UPDLOCK) WHERE ... And see MSSQL docu, chapter "Locking Hints", for details about content of WITH clause. TABLOCK may be interesting for you. 2) See SP_LOCK system procedure. It returns info about current locks in system. Regards, Dmitry -- Dmitry L. Arefiev, gs-soft Company, http://www.gs-soft.com Personal - http://www.da-soft.com SAPx - Delphi to SAP R/3 direct access Saphir - SAP R/3 metadata on your fingertips MetaBase - ERWIN model in Delphi applications GISx - GIS system booster and simplifier NCOCI8 - Freeware Delphi to ORACLE direct access SCard - Complete PKCS11 and X509 solution Back to top Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First         BorlandTalk.com Forum Index -> Delphi Databases (SQL Servers) All times are GMT Page 1 of 1   Jump to: Select a forum C++ Builder Newsgroups----------------C++ BuilderC++ Builder (ActiveX)C++ Builder (Announcements)C++ Builder (Command Line Tools)C++ Builder DatabasesC++ Builder Databases (ADO)C++ Builder Databases (Desktop)C++ Builder Databases (InterBase Express)C++ Builder Databases (Multi-Tier)C++ Builder Databases (SQL Servers)C++ Builder (Graphics)C++ Builder (IDE)C++ Builder (Internet)C++ Builder (Internet Socket)C++ Builder (Internet Web)C++ Builder (Jobs)C++ Builder (Language)C++ Builder (Language C++)C++ Builder (Compatibility with MFC)C++ Builder (Native API)C++ Builder (Non-Technical)C++ Builder (Students)C++ Builder (Third Party Tools)C++ Builder (Upgrade)C++ Builder (VCL)C++ Builder (VCL Components Usage)C++ Builder (VCL Components Development)C++ Builder (VCL Usage)C++ Builder (WinAPI)C++ Builder Installation Delphi Newsgroups----------------Delphi (General)Delphi ActiveX Controls UsageDelphi ActiveX Controls DevelopmentDelphi As400Delphi DatabasesDelphi Databases (ADO)Delphi Databases (dbExpress)Delphi Databases (Desktop)Delphi Databases (InterBase Express)Delphi Databases (Multi-Tier)Delphi Databases (SQL Servers)Delphi DeploymentDelphi GraphicsDelphi IDEDelphi InternationalizationDelphi InternetDelphi Internet Isapi-WebBrokerDelphi Internet WebSnapDelphi Internet WinsockDelphi JobsDelphi Language BASMDelphi Language ObjectPascalDelphi Model Driven Architecture (General)Delphi Model Driven Architecture (Third Party)Delphi MultimediaDelphi Native APIDelphi Non-TechnicalDelphi ObjectPascalDelphi OLE AutomationDelphi OO designDelphi OpenToolsAPIDelphi Reporting-ChartingDelphi RTLDelphi StudentsDelphi TeamSourceDelphi Thirdparty ToolsDelphi Thirdparty Tools (General)Delphi Thirdparty Tools (IntraWeb)Delphi Thirdparty Tools (RaveReports)Delphi UpgradeDelphi VCLDelphi VCL ComponentsDelphi VCL Components UsingDelphi VCL Components WritingDelphi WebServices SOAPDelphi WinAPIDelphi XMLDelphi Installationcomp.lang.pascal.delphi.components.misccomp.lang.pascal.delphi.components.usagecomp.lang.pascal.delphi.components.writingcomp.lang.pascal.delphi.databasescomp.lang.pascal.delphi.misccomp.sources.delphi JBuilder Newsgroups----------------JBuilderJBuilder AnnouncementsJBuilder Applet IssuesJBuilder As400JBuilder CompilerJBuilder CORBA/RMIJBuilder DatabasesJBuilder DB SwingJBuilder DebuggerJBuilder DeploymentJBuilder DocumentationJBuilder EnterpriseJBuilder HandheldJBuilder IDEJBuilder JavaJBuilder JavaAPIJBuilder Java LanguageJBuilder Java SwingJBuilder Java BeansJBuilder Java Beans UsageJBuilder Java Beans DevelopmentJBuilder JBCLJBuilder JDataStoreJBuilder JobsJBuilder LinuxJBuilder MacintoshJBuilder & MobileSetJBuilder MultiLingual AppsJBuilder Non-TechnicalJBuilder OpenToolsJBuilder Servlets (JSP)JBuilder StudentsJBuilder Team DevelopmentJBuilder Thirdparty ToolsJBuilder UpgradeJBuilder Installation InterBase Newsgroups----------------InterBaseInterBase Bug DiscussionInterBase GeneralInterBase IBConsoleInterBase OpenSourceInterBase ReplicationInterBase SQLInterBase ThirdpartyInterBase Installation Miscellaneous Borland Newsgroups----------------AppCenterAppServerEnteraVisiBroker  You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum Powered by phpBB © 2001, 2006 phpBB Group SEO toolkit © 2004-2006 webmedic.