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The following page has been changed by JonathanEllis: http://wiki.apache.org/cassandra/API The comment on the change is: describe methods ------------------------------------------------------------------------------ ||`column`||`Column`||n/a||N||The `Column` returned by `get()` or `get_slice()`.|| ||`super_column`||`SuperColumn`||n/a||N||The `SuperColumn` returned by `get()` or `get_slice()`.|| + === BatchMutation === + + ||'''Attribute'''||'''Type'''||'''Default'''||'''Required'''||'''Description'''|| + ||`key`||`string`||n/a||H||The key to insert data for.|| + ||`cfmap`||`map<string, list<ColumnOrSuperColumn>>`||n/a||N||A map of column family names to `ColumnOrSuperColumn` objects to insert in that !ColumnFamily.|| + == Method calls == - TODO + === get === + `ColumnOrSuperColumn get(keyspace, key, column_path, consistency_level)` + + Get the `Column` or `SuperColumn` at the given `column_path`. If no value is present, NotFoundException is thrown. (This is the only method that can throw an exception under non-failure conditions.) + + === get_slice === + `list<ColumnOrSuperColumn> get_slice(keyspace, key, column_parent, predicate, consistency_level)` + + Get the group of columns contained by `column_parent` (either a !ColumnFamily name or a !ColumnFamily/!SuperColumn name pair) specified by the given `predicate`. If no matching values are found, an empty list is returned. + + === multiget === + `map<string,ColumnOrSuperColumn> multiget(keyspace, keys, column_path, consistency_level)` + list<string> + + Perform a `get` for `column_path` in parallel on the given `list<string> keys`. The return value maps keys to the `ColumnOrSuperColumn` found. If no value corresponding to a key is present, the key will still be in the map, but both the `column` and `super_column` references of the `ColumnOrSuperColumn` object it maps to will be null. + + === multiget_slice === + `map<string,list<ColumnOrSuperColumn>> multiget_slice(keyspace, keys, column_parent, predicate, consistency_level)` + + Performs a `get_slice` for `column_parent` and `predicate` for the given keys in parallel. + + === get_count === + `i32 get_count(keyspace, key, column_parent, consistency_level)` + + Counts the columns present in `column_parent`. + + === get_key_range === + `list<string> get_key_range(keyspace, column_family, start, finish, count=100, consistency_level)` + + Returns a list of keys starting with `start`, ending with `finish`, and at most `count` long. (The semantics are similar to the corresponding components of `SliceRange`.) This method is only allowed when using an order-preserving partitioner. + + === insert === + `insert(keyspace, key, column_path, value, timestamp, consistency_level)` + + Insert a `Column` consisting of (`column_path.column`, `value`, `timestamp`) at the given `column_path.column_family` and optional `column_path.super_column`. Note that `column_path.column` is here required, since a !SuperColumn cannot directly contain binary values -- it con only contain sub-Columns. + + `batch_insert(keyspace, batch_mutation, consistency_level)` + + Insert the given `batch_mutation`, which is alone among methods here in containing its own key. + + `remove(keyspace, key, column_path, timestamp, consistency_level)` + + Remove data from the row specified by `key` at the granularity specified by `column_path`, and the given `timestamp`. Note that all the values in `column_path` besides `column_path.column_family` are truly optional: you can remove the entire row by just specifying the !ColumnFamily, or you can remove a !SuperColumn or a single Column by specifying those levels too. == Examples == - Would someone public-spirited add some examples of the results you'd get with these methods? + TODO (contributions welcome)
