When is cost based optimization triggered? (for DBA)
It's important to have statistics on all tables for the CBO (Cost Based Optimizer) to work correctly. If one table involved in a statement does not have statistics, Oracle has to revert to rule-based optimization for that statement. So you really want for all tables to have statistics right away; it won't help much to just have the larger tables analyzed.
Generally, the CBO can change the execution plan when you:
1. Change statistics of objects by doing an ANALYZE;
2. Change some initialization parameters (for example: hash_join_enabled, sort_area_size, db_file_multiblock_read_count).
It's important to have statistics on all tables for the CBO (Cost Based Optimizer) to work correctly. If one table involved in a statement does not have statistics, Oracle has to revert to rule-based optimization for that statement. So you really want for all tables to have statistics right away; it won't help much to just have the larger tables analyzed.
Generally, the CBO can change the execution plan when you:
1. Change statistics of objects by doing an ANALYZE;
2. Change some initialization parameters (for example: hash_join_enabled, sort_area_size, db_file_multiblock_read_count).
How can one optimize %XYZ% queries? (for DBA)
It is possible to improve %XYZ% queries by forcing the optimizer to scan all the entries from the index instead of the table. This can be done by specifying hints. If the index is physically smaller than the table (which is usually the case) it will take less time to scan the entire index than to scan the entire table.
It is possible to improve %XYZ% queries by forcing the optimizer to scan all the entries from the index instead of the table. This can be done by specifying hints. If the index is physically smaller than the table (which is usually the case) it will take less time to scan the entire index than to scan the entire table.
What Enter package procedure does ?
Enter Validate-data in the current validation unit.
Enter Validate-data in the current validation unit.
When should one rebuild an index? (for DBA)
You can run the 'ANALYZE INDEX VALIDATE STRUCTURE' command on the affected indexes - each invocation of this command creates a single row in the INDEX_STATS view. This row is overwritten by the next ANALYZE INDEX command, so copy the contents of the view into a local table after each ANALYZE. The 'badness' of the index can then be judged by the ratio of 'DEL_LF_ROWS' to 'LF_ROWS'.
You can run the 'ANALYZE INDEX VALIDATE STRUCTURE' command on the affected indexes - each invocation of this command creates a single row in the INDEX_STATS view. This row is overwritten by the next ANALYZE INDEX command, so copy the contents of the view into a local table after each ANALYZE. The 'badness' of the index can then be judged by the ratio of 'DEL_LF_ROWS' to 'LF_ROWS'.
What are the unrestricted procedures used to change the popup screen position during run time ?
Anchor-view
Resize -View
Move-View.
Anchor-view
Resize -View
Move-View.
What is an Alert ?
An alert is window that appears in the middle of the screen overlaying a portion of the current display.
An alert is window that appears in the middle of the screen overlaying a portion of the current display.
Deleting a page removes information about all the fields in that page ?
a. True. b. False
a. True.
a. True. b. False
a. True.
Two popup pages can appear on the screen at a time ?Two popup pages can appear on the screen at a time ?
a. True. b. False?
a. True.
a. True. b. False?
a. True.
Classify the restricted and unrestricted procedure from the following.
a. Call
b. User-Exit
c. Call-Query
d. Up
e. Execute-Query
f. Message
g. Exit-From
h. Post
i. Break?
a. Call - unrestricted
b. User Exit - Unrestricted
c. Call_query - Unrestricted
d. Up - Restricted
e. Execute Query - Restricted
f. Message - Restricted
g. Exit_form - Restricted
h. Post - Restricted
i. Break - Unrestricted.
a. Call
b. User-Exit
c. Call-Query
d. Up
e. Execute-Query
f. Message
g. Exit-From
h. Post
i. Break?
a. Call - unrestricted
b. User Exit - Unrestricted
c. Call_query - Unrestricted
d. Up - Restricted
e. Execute Query - Restricted
f. Message - Restricted
g. Exit_form - Restricted
h. Post - Restricted
i. Break - Unrestricted.
What is an User Exits ?
A user exit is a subroutine which are written in programming languages using pro*C pro *Cobol , etc., that link into the SQL * forms executable.
A user exit is a subroutine which are written in programming languages using pro*C pro *Cobol , etc., that link into the SQL * forms executable.
What is a Trigger ?
A piece of logic that is executed at or triggered by a SQL *forms event.
A piece of logic that is executed at or triggered by a SQL *forms event.
What is a Package Procedure ?
A Package procedure is built in PL/SQL procedure.
A Package procedure is built in PL/SQL procedure.
What is the maximum size of a form ?
255 character width and 255 characters Length.
255 character width and 255 characters Length.
What is the difference between system.current_field and system.cursor_field ?
1. System.current_field gives name of the field.
2. System.cursor_field gives name of the field with block name.
1. System.current_field gives name of the field.
2. System.cursor_field gives name of the field with block name.
List the system variables related in Block and Field?
1. System.block_status
2. System.current_block
3. System.current_field
4. System.current_value
5. System.cursor_block
6. System.cursor_field
7. System.field_status.
1. System.block_status
2. System.current_block
3. System.current_field
4. System.current_value
5. System.cursor_block
6. System.cursor_field
7. System.field_status.
What are the different types of Package Procedure ?
1. Restricted package procedure.
2. Unrestricted package procedure.
1. Restricted package procedure.
2. Unrestricted package procedure.
What are the types of TRIGGERS ?
1. Navigational Triggers.
2. Transaction Triggers.
1. Navigational Triggers.
2. Transaction Triggers.
Identify package function from the following ?
1. Error-Code
2. Break
3. Call
4. Error-text
5. Form-failure
6. Form-fatal
7. Execute-query
8. Anchor View
9. Message_code?
1. Error_Code
2. Error_Text
3. Form_Failure
4. Form_Fatal
5. Message_Code
1. Error-Code
2. Break
3. Call
4. Error-text
5. Form-failure
6. Form-fatal
7. Execute-query
8. Anchor View
9. Message_code?
1. Error_Code
2. Error_Text
3. Form_Failure
4. Form_Fatal
5. Message_Code
Can you attach an lov to a field at run-time? if yes, give the build-in name.?
Yes. Set_item_proprety
Yes. Set_item_proprety
Is it possible to attach same library to more than one form?
Yes
Yes
Can you attach an lov to a field at design time?
Yes
Yes
List the windows event triggers available in Forms 4.0?
When-window-activated,
when-window-closed,
when-window-deactivated,
when-window-resized
When-window-activated,
when-window-closed,
when-window-deactivated,
when-window-resized
What are the triggers associated with the image item?
When-Image-activated(Fires when the operator double clicks on an image Items)
When-image-pressed(fires when the operator selects or deselects the image item)
When-Image-activated(Fires when the operator double clicks on an image Items)
When-image-pressed(fires when the operator selects or deselects the image item)
What is a visual attribute?
Visual Attributes are the font, color and pattern characteristics of objects that operators see and intract with in our application.
Visual Attributes are the font, color and pattern characteristics of objects that operators see and intract with in our application.
How many maximum number of radio buttons can you assign to a radio group?
Unlimited no of radio buttons can be assigned to a radio group
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Unlimited no of radio buttons can be assigned to a radio group
What is Flex
Flex is the property of moving the related fields together by setting the flex property on
Flex is the property of moving the related fields together by setting the flex property on
What are the minimum number of groups required for a matrix report
The minimum of groups required for a matrix report are 4 e -----
The minimum of groups required for a matrix report are 4 e -----
What is a Synonym ?
A synonym is an alias for a table, view, sequence or program unit.
A synonym is an alias for a table, view, sequence or program unit.
What is a Sequence ?
A sequence generates a serial list of unique numbers for numerical columns of a database's tables.
A sequence generates a serial list of unique numbers for numerical columns of a database's tables.
What is a Segment ?
A segment is a set of extents allocated for a certain logical structure.
A segment is a set of extents allocated for a certain logical structure.
What is schema?
A schema is collection of database objects of a User.
A schema is collection of database objects of a User.
Describe Referential Integrity ?
A rule defined on a column (or set of columns) in one table that allows the insert or update of a row only if the value for the column or set of columns (the dependent value) matches a value in a column of a related table (the referenced value). It also specifies the type of data manipulation allowed on referenced data and the action to be performed on dependent data as a result of any action on referenced data.
A rule defined on a column (or set of columns) in one table that allows the insert or update of a row only if the value for the column or set of columns (the dependent value) matches a value in a column of a related table (the referenced value). It also specifies the type of data manipulation allowed on referenced data and the action to be performed on dependent data as a result of any action on referenced data.
What is Hash Cluster ?
A row is stored in a hash cluster based on the result of applying a hash function to the row's cluster key value. All rows with the same hash key value are stores together on disk.
A row is stored in a hash cluster based on the result of applying a hash function to the row's cluster key value. All rows with the same hash key value are stores together on disk.
What is a Private Synonyms ?
A Private Synonyms can be accessed only by the owner.
A Private Synonyms can be accessed only by the owner.
What is Database Link ?
A database link is a named object that describes a "path" from one database to another.
A database link is a named object that describes a "path" from one database to another.
What is index cluster?
A cluster with an index on the cluster key.
A cluster with an index on the cluster key.
What is hash cluster?
A row is stored in a hash cluster based on the result of applying a hash function to the row's cluster key value. All rows with the same hash key value are stores together on disk.
A row is stored in a hash cluster based on the result of applying a hash function to the row's cluster key value. All rows with the same hash key value are stores together on disk.
When can hash cluster used?
Hash clusters are better choice when a table is often queried with equality queries. For such queries the specified cluster key value is hashed. The resulting hash key value points directly to the area on disk that stores the specified rows.
Hash clusters are better choice when a table is often queried with equality queries. For such queries the specified cluster key value is hashed. The resulting hash key value points directly to the area on disk that stores the specified rows.
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