0
Want this question answered?
Be notified when an answer is posted
Add your answer:
Earn +20 pts
What is dql in Oracle?
Introduction to DQL -Documentum Query Language-The language used to query Documentum which is a content managementsystem used to create, manage, deliver, and archive all types of content from text documents and spreadsheets to digital images, HTML, and XML components.Contents• Define DQL• Behind the scenes• Describe a SELECT statement• Describe how search conditions are specified in a WHERE clause• Using DQL to search a specific cabinet/folder location• Describe the DQL REGISTER statementDQL (Documentum Query Language) is a query language which allows you to do very complex queries involving:1. Property searches2. Searches for words and phrases within documents3. Other specialized searching capabilities added for document and content managementDQL uses syntax that is a superset of ANSI-standard SQL (Structured Query Language)• In fact, part of your DQL statements are translated automatically into SQL before being executed by the eContent ServerBehind the Scenes• A DQL query is sent to the eContent Server using one of four API methodsreadquery, execquery, query, or cachequery• A DQL engine on eContent Server generates- SQL queries for the RDBMS- Verity queries for the full-text search engineThe results of the query are stored on the server in a non-persistent collectionobject. Typically, a Documentum client will automatically present the resultsof the query to the user in some useful way.Alternatively, a Developer may want to use the resulting collection object ormanipulate the results programmatically.Basic Select StatementSelect (list the properties you want returned)From (list the type of objects you want searched)Using WHERE clauseAllows the search to be narrowed by imposing search conditions on yourQueryselect [all | distinct] value [as name] {, value [as name] } from source_list[(all)]...[where qualification ]Eg :SELECT object_name, title FROM dm_document WHERE FOLDER (ID('0b9af3ce800001ff')) AND title LIKE '%SOP%'Searching folders and cabinetsThe scope of the search can be specified as folder and cabinet in the where clause to provide a way to search the cabinet/folder hierarchy.Eg : select object_name from dm_document where folder('/Sales')REGISTER statement• Registers an RDBMS table so the eContent Server can "see" it• Allows access to data in an existing RDBMS table that may be- created to support additional application data- part of another application- owned by someone else• Does not verify that the table or its columns exist• All columns in a table need not be registered• Creates a dm_registered object in the System cabinet whichprovides a description of the table and user access to itREGISTER permissions• Only the Docbase owner with a SUPERUSER privilege can register a table fromwithin Documentum.• To register a table, you must have at least READ permission on the table (through theRDBMS grant command).• The eContent Server account (installation owner) needs the appropriate RDBMSprivileges on the table to perform different operations on rows in the table.
How good is hemlock to burn for heatig your house as to other firewood types?
AnswerHere is a list of 50 or so different woods and their BTU/cord output. Hemlock ranks right below pine and comes in at 39th on the list.http:/www.chimneysweeponline.com/howood.htmALTERNATE ANSWERHemlock, like pine, spruce and other evergreen trees is dangerous to use for heating your house. The amount of creosote buildup in the chimney caused by burning these woods puts your house and your family in great danger from chimney fires. In addition, the sparks from evergreen trees can be dangerous as they go up the chimney and land on flammable areas of the house or yard. Evergreen sparks can burn a long time.REPLY TO ALTERNATE ANSWER:Any wood is safe to burn as long as it is seasoned. Creosote forms because of moisture content and colder temperatures up in your chimney. It has has nothing to do with wood type or sap. For example, what tree is tapped for sap? That's right, maple.I've supplemented my wood burning with hemlock for years and have never had a problem. No matter what wood your burn, you should sweep your chimney at least three times through the heating season. Anyway, hemlock has its redeeming values. First it seasons quickly. Second, it is great for getting the fire going (kindling and intermediate wood). Third, you can burn it on warmer fall, winter or spring days when you don't want the house to be 100 degrees because the coals don't last as long as hardwood. Also hemlock in a wood stove pops and crackles nicely. Mix it in with some hardwood and have a nice ambient fire that crackles and pops.The only potential danger with hemlock is the fact that it does pop and crackle nicely. If you are getting your firebox up to temperature with a lot of hemlock and you open your wood stove door, be careful. Hemlock throws sparks and pops off embers. Sometimes violently.In any event, it is a fine wood and has its place in heating my home.Re-ReplyHaving grown up in a small town in Maine beside the fire station, I can attest to the number of winter chimney fires due to people burning evergreen wood, pine, hemlock, cedar etc. The problems are:1. Most people are not as fastidious as you are in cleaning their chimney three times a buring season. Most people barely clean it once a year.2. Most people won't season it properly (leaving it outside on the ground in the shade under the porch etc does not season it)3. No matter how much you season it, you are only reducing its water content, not its pitch content. That snap crackle and pop which you enjoy is all the pitch exploding. And those sparks can go up the chimney and burn quite a while out in the air.4. Most people will not take the time (or have the skill) to work the fire correctly to keep the heat of the fire hot enough. There are times (beginning of the fire and end of the fire) when the heat is too low to sufficiently burn all the pitch residue5. And most people don't have a fire insert that burns the gases longer.Therefore, I stand by my first answer for the general public.THE TOPIC CONTINUES:Thank you for your reply. This debate is very important. But again, cresote has nothing to do with pitch, sap, or wood type. There is lots of info on the web regarding how creosote forms. Here are just a couple of links:http:/hearth.com/econtent/index.php/articles/creosote_from_wood_burning_causes_and_solutionshttp:/www.mastersweep.com/CREO.HTMCredible creosote discussions never mention wood-type as the culprit. It is wood moisture and cool flue temps.It's not my favorite, Hemlock, but I use being it's abundant where I live. Doug Fir or Maple then Alder followed by Hemlock.Cedar is a good hot burning wood but tends to snap crackle and pop abit and burns fast. I don't if I would classify wood as dangerous, well maybe when your falling them : ). Here's some other species I wouldn't consider unless it's the only choice, Cotton wood, Popular, all you end up with is stove full of ash and a little heat. On chimney cleaning. I have a real masonry chimney and burn dry wood pretty hot and I've cleaned my chimney once in 20 years and it wasn't to bad. I think when people start choking down the fire for a slow burn is when they run into the creosote issue along with burning wet wood.cheers
