It is possible to use raw devices as data files and what is the advantages over file. system files ?
Yes. The advantages over file system files. I/O will be improved because Oracle is bye-passing the kernnel which writing into disk. Disk Corruption will be very less.
Yes. The advantages over file system files. I/O will be improved because Oracle is bye-passing the kernnel which writing into disk. Disk Corruption will be very less.
What are disadvantages of having raw devices ?
We should depend on export/import utility for backup/recovery (fully reliable) The tar command cannot be used for physical file backup, instead we can use dd command which is less flexible and has limited recoveries.
We should depend on export/import utility for backup/recovery (fully reliable) The tar command cannot be used for physical file backup, instead we can use dd command which is less flexible and has limited recoveries.
What is the significance of having storage clause ?
We can plan the storage for a table as how much initial extents are required, how much can be extended next, how much % should leave free for managing row updations etc.,
We can plan the storage for a table as how much initial extents are required, how much can be extended next, how much % should leave free for managing row updations etc.,
What is the use of INCTYPE option in EXP command ?
Type export should be performed COMPLETE,CUMULATIVE,INCREMENTAL. List the sequence of events when a large transaction that exceeds beyond its optimal value when an entry wraps and causes the rollback segment toexpand into anotion Completes. e. will be written.
Type export should be performed COMPLETE,CUMULATIVE,INCREMENTAL. List the sequence of events when a large transaction that exceeds beyond its optimal value when an entry wraps and causes the rollback segment toexpand into anotion Completes. e. will be written.
What is the use of FILE option in IMP command ?
The name of the file from which import should be performed.
The name of the file from which import should be performed.
What is a Shared SQL pool?
The data dictionary cache is stored in an area in SGA called the Shared SQL Pool. This will allow sharing of parsed SQL statements among concurrent users.
The data dictionary cache is stored in an area in SGA called the Shared SQL Pool. This will allow sharing of parsed SQL statements among concurrent users.
What is hot backup and how it can be taken?
Taking backup of archive log files when database is open. For this the ARCHIVELOG mode should be enabled. The following files need to be backed up. All data files. All Archive log, redo log files. All control files.
Taking backup of archive log files when database is open. For this the ARCHIVELOG mode should be enabled. The following files need to be backed up. All data files. All Archive log, redo log files. All control files.
List the Optional Flexible Architecture (OFA) of Oracle database? or How can we organize the tablespaces in Oracle database to have maximum performance ?
SYSTEM - Data dictionary tables.
DATA - Standard operational tables.
DATA2- Static tables used for standard operations
INDEXES - Indexes for Standard operational tables.
INDEXES1 - Indexes of static tables used for standard operations.
TOOLS - Tools table.
TOOLS1 - Indexes for tools table.
RBS - Standard Operations Rollback Segments,
RBS1,RBS2 - Additional/Special Rollback segments.
TEMP - Temporary purpose tablespace
TEMP_USER - Temporary tablespace for users.
USERS - User tablespace.
SYSTEM - Data dictionary tables.
DATA - Standard operational tables.
DATA2- Static tables used for standard operations
INDEXES - Indexes for Standard operational tables.
INDEXES1 - Indexes of static tables used for standard operations.
TOOLS - Tools table.
TOOLS1 - Indexes for tools table.
RBS - Standard Operations Rollback Segments,
RBS1,RBS2 - Additional/Special Rollback segments.
TEMP - Temporary purpose tablespace
TEMP_USER - Temporary tablespace for users.
USERS - User tablespace.
How to implement the multiple control files for an existing database ?
Shutdown the database Copy one of the existing control file to new location Edit Config ora file by adding new control file. name Restart the database.
Shutdown the database Copy one of the existing control file to new location Edit Config ora file by adding new control file. name Restart the database.
What is advantage of having disk shadowing/ Mirroring ?
Shadow set of disks save as a backup in the event of disk failure. In most Operating System if any disk failure occurs it automatically switchover to place of failed disk. Improved performance because most OS support volume shadowing can direct file I/O request to use the shadow set of files instead of the main set of files. This reduces I/O load on the main set of disks.
Shadow set of disks save as a backup in the event of disk failure. In most Operating System if any disk failure occurs it automatically switchover to place of failed disk. Improved performance because most OS support volume shadowing can direct file I/O request to use the shadow set of files instead of the main set of files. This reduces I/O load on the main set of disks.
How will you force database to use particular rollback segment ?
SET TRANSACTION USE ROLLBACK SEGMENT rbs_name.
SET TRANSACTION USE ROLLBACK SEGMENT rbs_name.
Why query fails sometimes ?
Rollback segment dynamically extent to handle larger transactions entry loads. A single transaction may wipeout all available free space in the Rollback Segment Tablespace. This prevents other user using Rollback segments.
Rollback segment dynamically extent to handle larger transactions entry loads. A single transaction may wipeout all available free space in the Rollback Segment Tablespace. This prevents other user using Rollback segments.
What is the use of RECORD LENGTH option in EXP command ?
Record length in bytes.
Record length in bytes.
How will you monitor rollback segment status ?
Querying the DBA_ROLLBACK_SEGS view
IN USE - Rollback Segment is on-line.
AVAILABLE - Rollback Segment available but not on-line.
OFF-LINE - Rollback Segment off-line
INVALID - Rollback Segment Dropped.
NEEDS RECOVERY - Contains data but need recovery or corupted.
PARTLY AVAILABLE - Contains data from an unresolved transaction involving a distributed database.
Querying the DBA_ROLLBACK_SEGS view
IN USE - Rollback Segment is on-line.
AVAILABLE - Rollback Segment available but not on-line.
OFF-LINE - Rollback Segment off-line
INVALID - Rollback Segment Dropped.
NEEDS RECOVERY - Contains data but need recovery or corupted.
PARTLY AVAILABLE - Contains data from an unresolved transaction involving a distributed database.
What is meant by Redo Log file mirroring ? How it can be achieved?
Process of having a copy of redo log files is called mirroring. This can be achieved by creating group of log files together, so that LGWR will automatically writes them to all the members of the current on-line redo log group. If any one group fails then database automatically switch over to next group. It degrades performance.
Process of having a copy of redo log files is called mirroring. This can be achieved by creating group of log files together, so that LGWR will automatically writes them to all the members of the current on-line redo log group. If any one group fails then database automatically switch over to next group. It degrades performance.
Which parameter in Storage clause will reduce no. of rows per block?
PCTFREE parameter
Row size also reduces no of rows per block.
PCTFREE parameter
Row size also reduces no of rows per block.
What is meant by recursive hints ?
Number of times processes repeatedly query the dictionary table is called recursive hints. It is due to the data dictionary cache is too small. By increasing the SHARED_POOL_SIZE parameter we can optimize the size of Data Dictionary Cache.
Number of times processes repeatedly query the dictionary table is called recursive hints. It is due to the data dictionary cache is too small. By increasing the SHARED_POOL_SIZE parameter we can optimize the size of Data Dictionary Cache.
What is the use of PARFILE option in EXP command ?
Name of the parameter file to be passed for export.
Name of the parameter file to be passed for export.
What is the difference between locks, latches, enqueues and semaphores? (for DBA)
A latch is an internal Oracle mechanism used to protect data structures in the SGA from simultaneous access. Atomic hardware instructions like TEST-AND-SET is used to implement latches. Latches are more restrictive than locks in that they are always exclusive. Latches are never queued, but will spin or sleep until they obtain a resource, or time out.
Enqueues and locks are different names for the same thing. Both support queuing and concurrency. They are queued and serviced in a first-in-first-out (FIFO) order.
Semaphores are an operating system facility used to control waiting. Semaphores are controlled by the following Unix parameters: semmni, semmns and semmsl. Typical settings are:
semmns = sum of the "processes" parameter for each instance
(see init<instance>.ora for each instance)
semmni = number of instances running simultaneously;
semmsl = semmns
A latch is an internal Oracle mechanism used to protect data structures in the SGA from simultaneous access. Atomic hardware instructions like TEST-AND-SET is used to implement latches. Latches are more restrictive than locks in that they are always exclusive. Latches are never queued, but will spin or sleep until they obtain a resource, or time out.
Enqueues and locks are different names for the same thing. Both support queuing and concurrency. They are queued and serviced in a first-in-first-out (FIFO) order.
Semaphores are an operating system facility used to control waiting. Semaphores are controlled by the following Unix parameters: semmni, semmns and semmsl. Typical settings are:
semmns = sum of the "processes" parameter for each instance
(see init<instance>.ora for each instance)
semmni = number of instances running simultaneously;
semmsl = semmns
What is a logical backup?
Logical backup involves reading a set of database records and writing them into a file. Export utility is used for taking backup and Import utility is used to recover from backup.
Logical backup involves reading a set of database records and writing them into a file. Export utility is used for taking backup and Import utility is used to recover from backup.
Where can one get a list of all hidden Oracle parameters? (for DBA)
Oracle initialization or INIT.ORA parameters with an underscore in front are hidden or unsupported parameters. One can get a list of all hidden parameters by executing this query:
select *
from SYS.X$KSPPI
where substr(KSPPINM,1,1) = '_';
The following query displays parameter names with their current value:
select a.ksppinm "Parameter", b.ksppstvl "Session Value", c.ksppstvl "Instance Value"
from x$ksppi a, x$ksppcv b, x$ksppsv c
where a.indx = b.indx and a.indx = c.indx
and substr(ksppinm,1,1)='_'
order by a.ksppinm;
Remember: Thou shall not play with undocumented parameters!
Oracle initialization or INIT.ORA parameters with an underscore in front are hidden or unsupported parameters. One can get a list of all hidden parameters by executing this query:
select *
from SYS.X$KSPPI
where substr(KSPPINM,1,1) = '_';
The following query displays parameter names with their current value:
select a.ksppinm "Parameter", b.ksppstvl "Session Value", c.ksppstvl "Instance Value"
from x$ksppi a, x$ksppcv b, x$ksppsv c
where a.indx = b.indx and a.indx = c.indx
and substr(ksppinm,1,1)='_'
order by a.ksppinm;
Remember: Thou shall not play with undocumented parameters!
What is a database EVENT and how does one set it? (for DBA)
Oracle trace events are useful for debugging the Oracle database server. The following two examples are simply to demonstrate syntax. Refer to later notes on this page for an explanation of what these particular events do.
Either adding them to the INIT.ORA parameter file can activate events. E.g.
event='1401 trace name errorstack, level 12'
... or, by issuing an ALTER SESSION SET EVENTS command: E.g.
alter session set events '10046 trace name context forever, level 4';
The alter session method only affects the user's current session, whereas changes to the INIT.ORA file will affect all sessions once the database has been restarted.
Oracle trace events are useful for debugging the Oracle database server. The following two examples are simply to demonstrate syntax. Refer to later notes on this page for an explanation of what these particular events do.
Either adding them to the INIT.ORA parameter file can activate events. E.g.
event='1401 trace name errorstack, level 12'
... or, by issuing an ALTER SESSION SET EVENTS command: E.g.
alter session set events '10046 trace name context forever, level 4';
The alter session method only affects the user's current session, whereas changes to the INIT.ORA file will affect all sessions once the database has been restarted.
What is a Rollback segment entry ?
It is the set of before image data blocks that contain rows that are modified by a transaction. Each Rollback Segment entry must be completed within one rollback segment. A single rollback segment can have multiple rollback segment entries.
It is the set of before image data blocks that contain rows that are modified by a transaction. Each Rollback Segment entry must be completed within one rollback segment. A single rollback segment can have multiple rollback segment entries.
What database events can be set? (for DBA)
The following events are frequently used by DBAs and Oracle Support to diagnose problems:
" 10046 trace name context forever, level 4 Trace SQL statements and show bind variables in trace output.
" 10046 trace name context forever, level 8 This shows wait events in the SQL trace files
" 10046 trace name context forever, level 12 This shows both bind variable names and wait events in the SQL trace files
" 1401 trace name errorstack, level 12 1401 trace name errorstack, level 4 1401 trace name processstate Dumps out trace information if an ORA-1401 "inserted value too large for column" error occurs. The 1401 can be replaced by any other Oracle Server error code that you want to trace.
" 60 trace name errorstack level 10 Show where in the code Oracle gets a deadlock (ORA-60), and may help to diagnose the problem.
The following lists of events are examples only. They might be version specific, so please call Oracle before using them:
" 10210 trace name context forever, level 10 10211 trace name context forever, level 10 10231 trace name context forever, level 10 These events prevent database block corruptions
" 10049 trace name context forever, level 2 Memory protect cursor
" 10210 trace name context forever, level 2 Data block check
" 10211 trace name context forever, level 2 Index block check
" 10235 trace name context forever, level 1 Memory heap check
" 10262 trace name context forever, level 300 Allow 300 bytes memory leak for connections
Note: You can use the Unix oerr command to get the description of an event. On Unix, you can type "oerr ora 10053" from the command prompt to get event details.
The following events are frequently used by DBAs and Oracle Support to diagnose problems:
" 10046 trace name context forever, level 4 Trace SQL statements and show bind variables in trace output.
" 10046 trace name context forever, level 8 This shows wait events in the SQL trace files
" 10046 trace name context forever, level 12 This shows both bind variable names and wait events in the SQL trace files
" 1401 trace name errorstack, level 12 1401 trace name errorstack, level 4 1401 trace name processstate Dumps out trace information if an ORA-1401 "inserted value too large for column" error occurs. The 1401 can be replaced by any other Oracle Server error code that you want to trace.
" 60 trace name errorstack level 10 Show where in the code Oracle gets a deadlock (ORA-60), and may help to diagnose the problem.
The following lists of events are examples only. They might be version specific, so please call Oracle before using them:
" 10210 trace name context forever, level 10 10211 trace name context forever, level 10 10231 trace name context forever, level 10 These events prevent database block corruptions
" 10049 trace name context forever, level 2 Memory protect cursor
" 10210 trace name context forever, level 2 Data block check
" 10211 trace name context forever, level 2 Index block check
" 10235 trace name context forever, level 1 Memory heap check
" 10262 trace name context forever, level 300 Allow 300 bytes memory leak for connections
Note: You can use the Unix oerr command to get the description of an event. On Unix, you can type "oerr ora 10053" from the command prompt to get event details.
How can one dump internal database structures? (for DBA)
The following (mostly undocumented) commands can be used to obtain information about internal database structures.
o Dump control file contents
alter session set events 'immediate trace name CONTROLF level 10'
/
o Dump file headers
alter session set events 'immediate trace name FILE_HDRS level 10'
/
o Dump redo log headers
alter session set events 'immediate trace name REDOHDR level 10'
/
o Dump the system state
NOTE: Take 3 successive SYSTEMSTATE dumps, with 10-minute intervals alter session set events 'immediate trace name SYSTEMSTATE level 10'
/
o Dump the process state
alter session set events 'immediate trace name PROCESSSTATE level 10'
/
o Dump Library Cache details
alter session set events 'immediate trace name library cache level 10'
/
o Dump optimizer statistics whenever a SQL statement is parsed (hint: change statement or flush pool) alter session set events '10053 trace name context forever, level 1'
/
o Dump a database block (File/ Block must be converted to DBA address) Convert file and block number to a DBA (database block address).
Eg: variable x varchar2;
exec :x := dbms_utility.make_data_block_address(1,12);
print x
alter session set events 'immediate trace name blockdump level 50360894'
/
The following (mostly undocumented) commands can be used to obtain information about internal database structures.
o Dump control file contents
alter session set events 'immediate trace name CONTROLF level 10'
/
o Dump file headers
alter session set events 'immediate trace name FILE_HDRS level 10'
/
o Dump redo log headers
alter session set events 'immediate trace name REDOHDR level 10'
/
o Dump the system state
NOTE: Take 3 successive SYSTEMSTATE dumps, with 10-minute intervals alter session set events 'immediate trace name SYSTEMSTATE level 10'
/
o Dump the process state
alter session set events 'immediate trace name PROCESSSTATE level 10'
/
o Dump Library Cache details
alter session set events 'immediate trace name library cache level 10'
/
o Dump optimizer statistics whenever a SQL statement is parsed (hint: change statement or flush pool) alter session set events '10053 trace name context forever, level 1'
/
o Dump a database block (File/ Block must be converted to DBA address) Convert file and block number to a DBA (database block address).
Eg: variable x varchar2;
exec :x := dbms_utility.make_data_block_address(1,12);
print x
alter session set events 'immediate trace name blockdump level 50360894'
/
What are the different kind of export backups?
Full back - Complete database
Incremental - Only affected tables from last incremental date/full backup date.
Cumulative backup - Only affected table from the last cumulative date/full backup date.
Full back - Complete database
Incremental - Only affected tables from last incremental date/full backup date.
Cumulative backup - Only affected table from the last cumulative date/full backup date.
How free extents are managed in Ver 6.0 and Ver 7.0 ?
Free extents cannot be merged together in Ver 6.0.
Free extents are periodically coalesces with the neighboring free extent in Ver 7.0
Free extents cannot be merged together in Ver 6.0.
Free extents are periodically coalesces with the neighboring free extent in Ver 7.0
What is the use of RECORD option in EXP command?
For Incremental exports, the flag indirects whether a record will be stores data dictionary tables recording the export.
For Incremental exports, the flag indirects whether a record will be stores data dictionary tables recording the export.
What is the use of ROWS option in EXP command ?
Flag to indicate whether table rows should be exported. If 'N' only DDL statements for the database objects will be created.
Flag to indicate whether table rows should be exported. If 'N' only DDL statements for the database objects will be created.
What is the use of COMPRESS option in EXP command ?
Flag to indicate whether export should compress fragmented segments into single extents.
Flag to indicate whether export should compress fragmented segments into single extents.
How will you swap objects into a different table space for an existing database ?
Export the user
Perform import using the command imp system/manager file=export.dmp indexfile=newrite.sql.
This will create all definitions into newfile.sql. Drop necessary objects.
Run the script newfile.sql after altering the tablespaces.
Import from the backup for the necessary objects.
Export the user
Perform import using the command imp system/manager file=export.dmp indexfile=newrite.sql.
This will create all definitions into newfile.sql. Drop necessary objects.
Run the script newfile.sql after altering the tablespaces.
Import from the backup for the necessary objects.
How does Space allocation table place within a block ?
Each block contains entries as follows
Fixed block header
Variable block header
Row Header,row date (multiple rows may exists)
PCTEREE (% of free space for row updation in future)
Each block contains entries as follows
Fixed block header
Variable block header
Row Header,row date (multiple rows may exists)
PCTEREE (% of free space for row updation in future)
What are the factors causing the reparsing of SQL statements in SGA?
Due to insufficient Shared SQL pool size. Monitor the ratio of the reloads takes place while executing SQL statements. If the ratio is greater than 1 then increase the SHARED_POOL_SIZE. LOGICAL & PHYSICAL ARCHITECTURE OF DATABASE.
Due to insufficient Shared SQL pool size. Monitor the ratio of the reloads takes place while executing SQL statements. If the ratio is greater than 1 then increase the SHARED_POOL_SIZE. LOGICAL & PHYSICAL ARCHITECTURE OF DATABASE.
What is dictionary cache ?
Dictionary cache is information about the databse objects stored in a data dictionary table.
Dictionary cache is information about the databse objects stored in a data dictionary table.
What is a Control file ?
Database overall physical architecture is maintained in a file called control file. It will be used to maintain internal consistency and guide recovery operations. Multiple copies of control files are advisable.
Database overall physical architecture is maintained in a file called control file. It will be used to maintain internal consistency and guide recovery operations. Multiple copies of control files are advisable.
What is Database Buffers ?
Database buffers are cache in the SGA used to hold the data blocks that are read from the data segments in the database such as tables, indexes and clusters DB_BLOCK_BUFFERS parameter in INIT.ORA decides the size.
Database buffers are cache in the SGA used to hold the data blocks that are read from the data segments in the database such as tables, indexes and clusters DB_BLOCK_BUFFERS parameter in INIT.ORA decides the size.
How will you create multiple rollback segments in a database ?
Create a database which implicitly creates a SYSTEM Rollback Segment in a SYSTEM tablespace. Create a Second Rollback Segment name R0 in the SYSTEM tablespace. Make new rollback segment available (After shutdown, modify init.ora file and Start database) Create other tablespaces (RBS) for rollback segments. Deactivate Rollback Segment R0 and activate the newly created rollback segments.
Create a database which implicitly creates a SYSTEM Rollback Segment in a SYSTEM tablespace. Create a Second Rollback Segment name R0 in the SYSTEM tablespace. Make new rollback segment available (After shutdown, modify init.ora file and Start database) Create other tablespaces (RBS) for rollback segments. Deactivate Rollback Segment R0 and activate the newly created rollback segments.
What is cold backup? What are the elements of it?
Cold backup is taking backup of all physical files after normal shutdown of database. We need to take.
- All Data files.
- All Control files.
- All on-line redo log files.
- The init.ora file (Optional)
Cold backup is taking backup of all physical files after normal shutdown of database. We need to take.
- All Data files.
- All Control files.
- All on-line redo log files.
- The init.ora file (Optional)
What is meant by redo log buffer ?
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, they will first brought to redo log buffers in SGA and LGWR will write into files frequently. LOG_BUFFER parameter will decide the size.
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, they will first brought to redo log buffers in SGA and LGWR will write into files frequently. LOG_BUFFER parameter will decide the size.
How will you estimate the space required by a non-clustered tables?
Calculate the total header size
Calculate the available dataspace per data block
Calculate the combined column lengths of the average row
Calculate the total average row size.
Calculate the average number rows that can fit in a block
Calculate the number of blocks and bytes required for the table.
After arriving the calculation, add 10 % additional space to calculate the initial extent size for a working table.
Calculate the total header size
Calculate the available dataspace per data block
Calculate the combined column lengths of the average row
Calculate the total average row size.
Calculate the average number rows that can fit in a block
Calculate the number of blocks and bytes required for the table.
After arriving the calculation, add 10 % additional space to calculate the initial extent size for a working table.
How will you monitor the space allocation ?
By querying DBA_SEGMENT table/view.
By querying DBA_SEGMENT table/view.
What is meant by free extent ?
A free extent is a collection of continuous free blocks in tablespace. When a segment is dropped its extents are reallocated and are marked as free.
A free extent is a collection of continuous free blocks in tablespace. When a segment is dropped its extents are reallocated and are marked as free.
What is the use of IGNORE option in IMP command ?
A flag to indicate whether the import should ignore errors encounter when issuing CREATE commands.
A flag to indicate whether the import should ignore errors encounter when issuing CREATE commands.
What is the use of ANALYSE ( Ver 7) option in EXP command ?
A flag to indicate whether statistical information about the exported objects should be written to export dump file.
A flag to indicate whether statistical information about the exported objects should be written to export dump file.
What is the use of ROWS option in IMP command ?
A flag to indicate whether rows should be imported. If this is set to 'N' then only DDL for database objects will be executed.
A flag to indicate whether rows should be imported. If this is set to 'N' then only DDL for database objects will be executed.
What is the use of INDEXES option in EXP command ?
A flag to indicate whether indexes on tables will be exported.
A flag to indicate whether indexes on tables will be exported.
What is the use of INDEXES option in IMP command ?
A flag to indicate whether import should import index on tables or not.
A flag to indicate whether import should import index on tables or not.
What is the use of GRANT option in EXP command?
A flag to indicate whether grants on databse objects will be exported or not. Value is 'Y' or 'N'.
A flag to indicate whether grants on databse objects will be exported or not. Value is 'Y' or 'N'.
What is the use of GRANT option in IMP command ?
A flag to indicate whether grants on database objects will be imported.
A flag to indicate whether grants on database objects will be imported.
What is the use of FULL option in EXP command ?
A flag to indicate whether full databse export should be performed.
A flag to indicate whether full databse export should be performed.
What is the use of SHOW option in IMP command ?
A flag to indicate whether file content should be displayed or not.
A flag to indicate whether file content should be displayed or not.
What is the use of CONSTRAINTS option in EXP command ?
A flag to indicate whether constraints on table need to be exported.
A flag to indicate whether constraints on table need to be exported.
What is the use of CONSISTENT (Ver 7) option in EXP command ?
A flag to indicate whether a read consistent version of all the exported objects should be maintained.
A flag to indicate whether a read consistent version of all the exported objects should be maintained.
What are the different methods of backing up oracle database ?
- Logical Backups
- Cold Backups
- Hot Backups (Archive log)
- Logical Backups
- Cold Backups
- Hot Backups (Archive log)
What is the difference between ON-VALIDATE-FIELD trigger and a POST-CHANGE trigger ?
When you changes the Existing value to null, the On-validate field trigger will fire post change trigger will not fire. At the time of execute-query post-change trigger will fire, on-validate field trigger will not fire.
When you changes the Existing value to null, the On-validate field trigger will fire post change trigger will not fire. At the time of execute-query post-change trigger will fire, on-validate field trigger will not fire.
When is PRE-QUERY trigger executed ?
When Execute-query or count-query Package procedures are invoked.
When Execute-query or count-query Package procedures are invoked.
