A hash table in Java with 64-bit hash codes (ctd)Continuing our compact hash map implementation, we turn to the get() and set() methods. get() methodWe'll start by looking at how to implement the get() method, because this is more straightforward than the put() method and will ...
From now on, I will assume that you know what hash tables are. If you think you need to brush up your knowledge a bit, good references are either the “Hash table” article on Wikipedia[1](and the external links section at the bottom of the page), or the Hash table chapter in the...
For the descriptions of the three hash table libraries below, I will take as a common example a set of city names as keys, and their GPS coordinates as values. The source code for unordered_map can be found in GCC’s code, as part of libstdc++-v3. I’ll be looking at libstdc++-v...
One embodiment of the present invention provides a system that performs operations on a hash table that is fully dynamic and lock-free. This hash table is implemented with a linked list containing data nodes and a bucket array containing bucket pointers, wherein the bucket pointers point to ...
config.h.in configure.ac libhl C library implementing a set of APIs to efficiently manage some basic data structures such as : hashtables, linked lists, queues, trees, ringbuffers, red-black trees, priority queues, skip lists The provided APIs are : ...
full key data when the hashes match. If there are many exact collisions, then many unsuccessful retrieval of key data will be performed, wasting a lot of I/O. This metric depends only on the hash function, not on the hash table algorithm, which is why it is not included in this ...
Override the GetHashCode method to allow a type to work correctly in a hash table. Do not throw an exception in the implementation of an Equals method. Instead, return false for a null argument. Follow the contract defined on the Object.Equals Method as follows: x.Equals(x) returns true...
Stringsql="""select name, role_name from t_users a left join t_roles b on a.role_id = b.idwhere a.id = 1""";printOptimizeBeforeAfter(sql,CoreRules.FILTER_INTO_JOIN);/*Before:LogicalProject(NAME=[$1], ROLE_NAME=[$4])LogicalFilter(condition=[=($0, 1)])LogicalJoin(condition=[...
Because of the semantics ofhash, if you overrideisEqual:then youmustoverridehash. If you don't, then you risk having two objects which are equal but which don't have the same hash. If you use these objects in a dictionary, set, or something else which uses a hash table, then hilarity...
这里为了实现简单,没有引入 database 与 schema 的概念,RootCatalog 下直接包含一个 HashMap 存放所有的 TableCatalog。TableCatalog 则包含所有的 ColumnCatalog。如下定义: pub struct RootCatalog { pub tables: HashMap<TableId, TableCatalog>, } pub struct TableCatalog { pub id: TableId, pub name: Stri...