Class BDB1::Common |
|
Methods |
Public Class methods |
type([hash]) |
create a new temporary db file, populated with the given object
type([bdb1]) |
same than type[hash]
create([name, flags, mode, options]) |
open the database
The argument name is used as the name of a single physical file on disk that will be used to back the database.
The flags value must be set to 0 or by bitwise inclusively OR'ing together one or more of the following values
Create any underlying files, as necessary. If the files do not already exist and the DB_CREATE flag is not specified, the call will fail.
Return an error if the database already exists. Underlying filesystem primitives are used to implement this flag. For this reason it is only applicable to the physical database file and cannot be used to test if a subdatabase already exists.
Do not map this database into process memory.
Open the database for reading only. Any attempt to modify items in the database will fail regardless of the actual permissions of any underlying files.
Physically truncate the underlying database file, discarding all previous subdatabases or databases. Underlying filesystem primitives are used to implement this flag. For this reason it is only applicable to the physical database file and cannot be used to discard subdatabases. The DB_TRUNCATE flag cannot be transaction protected, and it is an error to specify it in a transaction protected environment.
Open the database for writing. Without this flag, any attempt to modify items in the database will fail.
general database configuration
set the database cache size
set the underlying database page size
set the database byte order
specify a Proc called before a key is stored
specify a Proc called after a key is read
specify a Proc called before a value is stored
specify a Proc called after a value is read
specify a Btree comparison function
set the minimum number of keys per Btree page
specify a Btree prefix comparison function
set the Hash table density
specify a hashing function
set the Hash table size
Proc given to set_bt_compare, set_bt_prefix, set_h_hash, set_store_key, set_fetch_key, set_store_value and set_fetch_value can be also specified as a method (replace the prefix set_ with bdb1_)
For example
module BDB1 class Btreesort < Btree def bdb1_bt_compare(a, b) b.downcase <=> a.downcase end end end
new([name, flags, mode, options]) |
same than create
open([name, flags, mode, options]) |
same than create
Public Instance methods |
self([key]) |
Returns the value corresponding the key
db_get(key [, flags]) |
Returns the value correspondind the key
get(key [, flags]) |
same than db_get
fetch(key [, flags]) |
same than db_get
self([key] = value) |
Stores the value associating with key
return value
db_put(key, value [, flags]) |
Stores the value associating with key
Return the value correspondind the key
flags can have the value DBD::NOOVERWRITE, in this case it will return nil if the specified key exist, otherwise true
put(key, value [, flags]) |
same than db_put
store(key, value [, flags]) |
same than db_put
append(key, value) |
Append the value associating with key
db_append(key, value) |
same than append
byteswapped?() |
Return if the underlying database is in host order
get_byteswapped() |
same than byteswapped?
close([flags]) |
Closes the file.
db_close([flags]) |
same than close
delete(key) |
Removes the association from the key.
It return the object deleted or nil if the specified key don't exist.
db_del(key) |
same than delete
delete_if([set]) {|key, value| ...} |
Deletes associations if the evaluation of the block returns true.
Only for BDB1::Btree
reject!([set]) {|key, value| ...} |
same than delete_if
duplicates(key [, assoc = true]) |
Return an array of all duplicate associations for key
if assoc is false return only the values.
Only for BDB1::Btree
each() {|key, value| ...} |
Iterates over associations.
each_pair() {|key, value| ...} |
same than each { |key, value| ... }
each_dup(key) {|key, value| ...} |
Iterates over each duplicate associations for key
Only for BDB1::Btree
each_dup_value(key) {|value| ...} |
Iterates over each duplicate values for key
Only for BDB1::Btree
each_key() {|key| ...} |
Iterates over keys.
each_value() {|value| ...} |
Iterates over values.
empty?() |
Returns true if the database is empty.
has_key?(key) |
Returns true if the association from the key exists.
key?(key) |
same than has_key?
include?(key) |
same than has_key?
member?(key) |
same than has_key?
has_both?(key, value) |
Returns true if the association from key is value
both?(key, value) |
same than has_both?
has_value?(value) |
Returns true if the association to the value exists.
value?(value) |
same than has_value?
index(value) |
Returns the first key associated with value
indexes(value1, value2, ) |
Returns the keys associated with value1, value2, ...
keys() |
Returns the array of the keys in the database
length() |
Returns the number of association in the database.
size() |
same than length
reject() {|key, value| ...} |
Create an hash without the associations if the evaluation of the block returns true.
reverse_each() {|key, value| ...} |
Iterates over associations in reverse order
Only for BDB1::Btree
reverse_each_pair() {|key, value| ...} |
same than reverse_each { |key, value| ... }
reverse_each_key() {|key| ...} |
Iterates over keys in reverse order
Only for BDB1::Btree
reverse_each_value() {|value| ...} |
Iterates over values in reverse order.
Only for BDB1::Btree
to_a() |
Return an array of all associations [key, value]
to_hash() |
Return an hash of all associations {key => value}
truncate() |
Empty a database
clear() |
same than truncate
values() |
Returns the array of the values in the database.