Simply describe what is a DML statement is when you executed?
DML statements are executed when we adding new rows to the table. It executed when modifying the rows of a table and when removing rows from the table.
When inserting rows with Null values, what methods can be used?
The methods used for inserting rows with null values are,
• Implicit method
• Explicit method
Briefly describe how to creating a script that input value on SQL statement execution run times?
SQL scripts can be created using SQL editor. We can also pass the database information to the SQL as an input data at runtime. We can insert, update delete and retrieve rows from the database at runtime using SQL (Using INSERT, UPDATE and DELETE). Two modes can be used to create SQL scripts …show more content…
ERROR at line 1:
Ora-02292: integrity constraint
Violated – child record found
This error occurs when we are trying to delete rows which are referenced by another table. In this case we cannot delete rows from parent table if child table has rows which reference to the parent table.
Briefly describe what is explicit default feature?
With this feature we can use DEFAULT keyword as a column value whre the column default is desired. This allows the user to control where and when the default value should be applied to data. Explicit defaults can be used in INSERT and UPDATE statements.
Briefly describe what benefits to using merge statements?
MERGE statement is used to perform multiple DML operations. Benefit of MERGE statement is all the data read and processed only once. For INSERT, UPDATE or DELETE we have to use different statements to process. MERGE statement overcome this problem.
Briefly describe what is database transaction?
Database transaction is a sequence of operations performed as a single logical unit of work. That unit work exhibits four properties atomicity, consistency, isolation and durability properties to qualify as a
DML statements are executed when we adding new rows to the table. It executed when modifying the rows of a table and when removing rows from the table.
When inserting rows with Null values, what methods can be used?
The methods used for inserting rows with null values are,
• Implicit method
• Explicit method
Briefly describe how to creating a script that input value on SQL statement execution run times?
SQL scripts can be created using SQL editor. We can also pass the database information to the SQL as an input data at runtime. We can insert, update delete and retrieve rows from the database at runtime using SQL (Using INSERT, UPDATE and DELETE). Two modes can be used to create SQL scripts …show more content…
ERROR at line 1:
Ora-02292: integrity constraint
Violated – child record found
This error occurs when we are trying to delete rows which are referenced by another table. In this case we cannot delete rows from parent table if child table has rows which reference to the parent table.
Briefly describe what is explicit default feature?
With this feature we can use DEFAULT keyword as a column value whre the column default is desired. This allows the user to control where and when the default value should be applied to data. Explicit defaults can be used in INSERT and UPDATE statements.
Briefly describe what benefits to using merge statements?
MERGE statement is used to perform multiple DML operations. Benefit of MERGE statement is all the data read and processed only once. For INSERT, UPDATE or DELETE we have to use different statements to process. MERGE statement overcome this problem.
Briefly describe what is database transaction?
Database transaction is a sequence of operations performed as a single logical unit of work. That unit work exhibits four properties atomicity, consistency, isolation and durability properties to qualify as a