What is a SNAPSHOT LOG ?

What is a SNAPSHOT LOG ?
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1 Answer

Answer :

A snapshot log is a table in the master database that is associated with
the master table. ORACLE uses a snapshot log to track the rows that have been updated in the master table. Snapshot logs are used in updating the snapshots based on the master table.
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Related questions

What is snapshot log ?

Description : What is snapshot log ?

Last Answer : It is a table that maintains a record of modifications to the master table in a snapshot. It is stored in the same database as master table and is only available for simple snapshots. It should be created before creating snapshots.

When will the data in the snapshot log be used?

Description : When will the data in the snapshot log be used?

Last Answer : We must be able to create a after row trigger on table (i.e., it should be not be already available) After giving table privileges. We cannot specify snapshot log name because oracle uses the ... 23 characters. (The table name created will be MLOGS_tablename, and trigger name will be TLOGS name).

What is a SNAPSHOT ?

Description : What is a SNAPSHOT ?

Last Answer : Snapshots are read-only copies of a master table located on a remote node which is periodically refreshed to reflect changes made to the master table.

What is ORA-01555 - Snapshot Too Old error and how do you avoid it?

Description : What is ORA-01555 - Snapshot Too Old error and how do you avoid it?

Last Answer : The ORA-01555 is caused by Oracle read consistency mechanism. If you have a long running SQL that starts at 11:30 AM, Oracle ensures that all rows are as they appeared at 11:30 AM, ... -01555 snapshot too old also relates to your setting for automatic undo retention ▪ Don't fetch between commits

What is ORA-01555 - Snapshot Too Old error and how do you avoid it?

Description : What is ORA-01555 - Snapshot Too Old error and how do you avoid it?

Last Answer : The ORA-01555 is caused by Oracle read consistency mechanism. If you have a long running SQL that starts at 11:30 AM, Oracle ensures that all rows are as they appeared at 11:30 AM, ... -01555 snapshot too old also relates to your setting for automatic undo retention ▪ Don't fetch between commits

How would you force a log switch?

Description : How would you force a log switch?

Last Answer : ALTER SYSTEM SWITCH LOGFILE;

What is the use of redo log information?

Description : What is the use of redo log information?

Last Answer : The information in a redo log file is used only to recover the database from a system or media failure prevents database data from being written to a database's data files.

What is the function of redo log?

Description : What is the function of redo log?

Last Answer : The primary function of the redo log is to record all changes made to data.

What is a redo log?

Description : What is a redo log?

Last Answer : The set of redo log files for a database is collectively known as the database redo log.

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Description : What is Archived Redo Log ?

Last Answer : Archived Redo Log consists of Redo Log files that have archived before being reused.

What is On-line Redo Log?

Description : What is On-line Redo Log?

Last Answer : The On-line Redo Log is a set of tow or more on-line redo files that record all committed changes made to the database. Whenever a transaction is committed, the corresponding redo entries temporarily ... file by the background process LGWR. The on-line redo log files are used in cyclical fashion.

What is Log Switch ?

Description : What is Log Switch ?

Last Answer : The point at which ORACLE ends writing to one online redo log file and begins writing to another is called a log switch.

What is meant by redo log buffer ?

Description : What is meant by redo log buffer ?

Last Answer : Changes made to entries are written to the on-line redo log files. So that they can be used in roll forward operations during database recoveries. Before writing them into the redo log files ... buffers in SGA and LGWR will write into files frequently. LOG_BUFFER parameter will decide the size.

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How does one backup archived log files? (for DBA

Description : How does one backup archived log files? (for DBA

Last Answer : One can backup archived log files using RMAN or any operating system backup utility. Remember to delete files after backing them up to prevent the archive log directory from filling up. If the ... oracle/arch_backup/log_t%t_s%s_p%p' 5> (archivelog all delete input); 6> release channel dev1; 7> }

How can we specify the Archived log file name format and destination?

Description : How can we specify the Archived log file name format and destination?

Last Answer : By setting the following values in init.ora file. LOG_ARCHIVE_FORMAT = arch %S/s/T/tarc (%S - Log sequence number and is zero left paded, %s - Log sequence number not padded. %T - Thread number lef ... not padded). The file name created is arch 0001 are if %S is used. LOG_ARCHIVE_DEST = path.

What is a Redo Log ?

Description : What is a Redo Log ?

Last Answer : The set of Redo Log files YSDATE,UID,USER or USERENV SQL functions,or the pseudo columns LEVEL or ROWNUM.

What is Mirrored on-line Redo Log ?

Description : What is Mirrored on-line Redo Log ?

Last Answer : A mirrored on-line redo log consists of copies of on-line redo log files physically located on separate disks, changes made to one member of the group are made to all members.

What are database files, control files and log files. How many of these files should a database have at least? Why?

Description : What are database files, control files and log files. How many of these files should a database have at least? Why?

Last Answer : ∙ Database Files The database files hold the actual data and are typically the largest in size. Depending on their sizes, the tables (and other objects) for all the user accounts can go in one ... or redo log file to the database, the information is recorded in the control files. ∙ Redo Logs

What is the purpose of Redo Log files?

Description : What is the purpose of Redo Log files?

Last Answer : Before Oracle changes data in a datafile it writes these changes to the redo log. If something happens to one of the datafiles, a backed up datafile can be restored and the redo, that was written since, replied, which brings the datafile to the state it had before it became unavailable.

Which log would you check if a database has a problem?

Description : Which log would you check if a database has a problem?

Last Answer : Alert log

Did you take a snapshot today? Want to share it?

Description : Did you take a snapshot today? Want to share it?

Last Answer : I took this this morning and chuckled to myself “Fat Barry on Fat Tuesday”....my dad once referred to my cat Barnabus as Fat Barry and I laugh hysterically every time I call him that. Not sure why.

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Is there a free program that allows me to take a snapshot of whatever is on my computer screen?

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Last Answer : first of all, which OS ?

Can anyone send me the link to the official Minecraft 1.17 snapshot website most people use?

Description : Can anyone send me the link to the official Minecraft 1.17 snapshot website most people use?

Last Answer : By most people, I mean like the youtubers.

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Description : Report snapshot:

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What is Snapshot parameter in SSRS?

Description : What is Snapshot parameter in SSRS?

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Description : What is report snapshot in SSRS?

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Last Answer : D) Refresh

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Description : How does one use the import/export utilities? (for DBA

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what is a display item?

Description : what is a display item?

Last Answer : Display items are similar to text items but store only fetched or assigned values. Operators cannot navigate to a display item or edit the value it contains.

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Description : Are there any troubleshooting tips for OEM? (for DBA

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Description : Where can one get more information about TCL? (for DBA

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How does one start the Oracle Intelligent Agent? (for DBA

Description : How does one start the Oracle Intelligent Agent? (for DBA

Last Answer : One needs to start an OIA (Oracle Intelligent Agent) process on all machines that will to be managed via OEM. For OEM 9i and above:

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Description : What is the Oracle Intelligent Agent? (for DBA

Last Answer : The Oracle Intelligent Agent (OIA) is an autonomous process that needs to run on a remote node in the network to make the node OEM manageable. The Oracle Intelligent Agent is ... events registered in Enterprise Manager; and . Executing tasks associated with jobs submitted to Enterprise Manager.

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Description : What are the types of SQL Statement ?

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Description : What are the pre requisites ?

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What kind of jobs can one schedule with OEM? (for DBA

Description : What kind of jobs can one schedule with OEM? (for DBA

Last Answer : OEM comes with pre-defined jobs like Export, Import, run OS commands, run sql scripts, SQL*Plus commands etc. It also gives you the flexibility of scheduling custom jobs written with the TCL language.

Difference between SUBSTR and INSTR ?

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Description : Should the OEM Console be displayed at all times (when there are scheduled jobs)? (for DBA

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Explain UNION,MINUS,UNION ALL, INTERSECT ?

Description : Explain UNION,MINUS,UNION ALL, INTERSECT ?

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Description : WHY USE RMAN ? (for DBA

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