MongoDB

&reftitle.intro; Instances of this class are used to interact with a database. To get a database: selectDB("example"); ?> ]]> Database names can use almost any character in the ASCII range. However, they cannot contain " ", "." or be the empty string. The name "system" is also reserved. A few unusual, but valid, database names: "null", "[x,y]", "3", "\"", "/". Unlike collection names, database names may contain "$".

&reftitle.classsynopsis; MongoDB MongoDB &Constants; const int MongoDB::PROFILING_OFF 0 const int MongoDB::PROFILING_SLOW 1 const int MongoDB::PROFILING_ON 2 Fields public integer w 1 public integer wtimeout 10000 &Methods;

&reftitle.constants;

MongoDB::PROFILING_OFF 0 Profiling is off. MongoDB::PROFILING_SLOW 1 Profiling is on for slow operations (>100 ms). MongoDB::PROFILING_ON 2 Profiling is on for all operations.

w 1 The number of servers to replicate a change to before returning success. Inherited by instances of MongoCollection derived from this. w functionality is only available in version 1.5.1+ of the MongoDB server and 1.0.8+ of the driver. w is used whenever you need to adjust the acknowledgement level (MongoCollection::insert, MongoCollection::update, MongoCollection::remove, MongoCollection::save, and MongoCollection::ensureIndex all support this option). With the default value (1), an acknowledged operation will return once the database server has the operation. If the server goes down before the operation has been replicated to a secondary, it is possible to lose the operation forever. Thus, you can specify w to be higher than one and guarantee that at least one secondary has the operation before it is considered successful. For example, if w is 2, the primary and one secondary must have a record of the operation or the driver will throw a MongoCursorException. It is tempting to set w to the total number of secondaries + primary, but then if one secondary is down the operation will fail and an exception will be thrown, so usually w=2 is safest (primary and one secondary). wtimeout 10000 The number of milliseconds to wait for MongoDB::$w replications to take place. Inherited by instances of MongoCollection derived from this. w functionality is only available in version 1.5.1+ of the MongoDB server and 1.0.8+ of the driver. Unless wtimeout is set, the server waits forever for replicating to w servers to finish. The driver defaults to waiting for 10 seconds, you can change this value to alter its behavior.

&reftitle.seealso; MongoDB core docs on databases.

&reference.mongo.entities.mongodb;