Updating statistics in oracle

ARCHIVELOG mode is a mode that you can put the database in for creating a backup of all transactions that have occurred in the database so that you can recover to any point in time. Candidate should mention use of DECLARE statement, a function must return a value while a procedure doesn't have to. What is a mutating table error and how can you get around it? It occurs because the trigger is trying to update a row it is currently using.

NOARCHIVELOG mode is basically the absence of ARCHIVELOG mode and has the disadvantage of not being able to recover to any point in time. Where in the Oracle directory tree structure are audit traces placed? The usual fix involves either use of views or temporary tables so the database is selecting from one while updating the other. Describe the use of %ROWTYPE and %TYPE in PL/SQL Expected answer: %ROWTYPE allows you to associate a variable with an entire table row.

A hot backup is basically taking a backup of the database while it is still up and running and it must be in archive log mode.

A cold backup is taking a backup of the database while it is shut down and does not require being in archive log mode.

Or if the ratio BR_BLK_LEN/ LF_BLK_LEN BR_BLK_LEN is nearing 0.3. How can variables be passed to a SQL routine By use of the & symbol.

In addition, since you are taking cold backups the database does not require being in archive log mode and thus there will be a slight performance gain as the database is not cutting archive logs to disk.

A data block is the smallest unit of logical storage for a database object.

For passing in variables the numbers 1-8 can be used (&1, &2,...,&8) to pass the values after the command into the SQLPLUS session. What SQLPlus command is used to format output from a select This is best done with the COLUMN command. You want to group the following set of select returns, what can you group on Max(sum_of_cost), min(sum_of_cost), count(item_no), item_no The only column that can be grouped on is the "item_no" column, the rest have aggregate functions associated with them. What special Oracle feature allows you to specify how the cost based system treats a SQL statement The COST based system allows the use of HINTs to control the optimizer path selection.

To be prompted for a specific variable, place the ampersanded variable in the code itself: "select * from dba_tables where owner=&owner_name;" . ); spool off Essentially you are looking to see that they know to include a command (in this case DROP USER... If they can give some example hints such as FIRST ROWS, ALL ROWS, USING INDEX, STAR, even better. You want to determine the location of identical rows in a table before attempting to place a unique index on the table, how can this be done Oracle tables always have one guaranteed unique column, the rowid column.

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