Search for	Example	Results
A single word	`cat`	Topics that contain the word "cat". You will also find its grammatical variations, such as "cats".
A phrase. You can specify that the search results contain a specific phrase.	`"cat food"` (quotation marks)	Topics that contain the literal phrase "cat food" and all its grammatical variations. Without the quotation marks, the query is equivalent to specifying an OR operator, which finds topics with one of the individual words instead of the phrase.

Search for	Operator	Example
Two or more words in the same topic	`AND` `and` `+` (plus symbol) `&` (ampersand)	`cat AND dog` `"cat food"+milk` `"cat food"&"dog food"`
Either word in a topic	`OR` `or` `\|` (pipe)	`cat OR dog` `cat \| dog`
Topics that do not contain a specific word or phrase	`NOT` `not` `!` (exclamation point)	`NOT cat` `! dog`
Topics that contain one string and do not contain another	`^` (caret)	`cat ^ mouse`
A combination of search types	`( )` parentheses	`cat + (dog \| mouse)` `cat \| dog + (! mouse)`

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Use > Database > Deploying the Oracle Server Database > Oracle Server Configuration and Sizing Guidelines > Using RAID Configuration

Using RAID Configuration

The use of RAID is transparent to Oracle. All the features specific to RAID configurations are handled by the operating system and not by Oracle.

The use of RAID devices differs according to the Oracle file type. Data files and archive logs can be placed on RAID devices, since they are accessed randomly. Redo logs should not be put on RAID devices, since they are accessed sequentially and performance is enhanced by having the disk drive head near the last write location. However, mirroring of redo log files is strongly recommended by Oracle.

RAID is much easier to use than the Oracle techniques for data placement and striping.

Note the following RAID configuration recommendations:

RAID usually impacts write operations more than read operations. This is especially true where parity needs to be calculated (RAID 3, RAID 5, and so forth).
You can place online or archived redo log files on RAID 1 devices. Do not use RAID 5. In addition, place TEMP tablespace data files on RAID 1 devices, instead of RAID 5, because the streamed write performance of distributed parity (RAID 5) is not as good as that of simple mirroring (RAID 1).
Swap space can be used on RAID devices without affecting Oracle.

The following table describes the RAID devices and types to be used with each Oracle file type:

RAID	Type of RAID	Control File	Database File	Redo Log File/Temporary	Archive File
0	Striping	Avoid	OK	Avoid	Avoid
1	Shadowing	OK	OK	Recommended	Recommended
0+1	Striping + Shadowing	OK	Recommended	Avoid	Avoid
3	Striping with static parity	OK	Avoid when this data file involves heavy write operation	Avoid	Avoid
5	Striping with rotating parity	OK	Avoid when this data file involves heavy write operation	Avoid	Avoid

Note

RAID 0 does not provide protection against failures. It requires a strong backup strategy.
RAID 0+1 is recommended for database files because it avoids hot spots and provides the best possible performance during a disk failure. The disadvantage of RAID 0+1 is its costly configuration.
Use the highest RPM disks for temporary/redo logs. Use as many controllers as you can in the array, and ensure that you place the redo log groups on different controllers.

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