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The HyperLogLog has three main operations: add to add a new element to the set, count to obtain the cardinality of the set and merge to obtain the union of two sets. Some derived operations can be computed using the inclusion–exclusion principle like the cardinality of the intersection or the cardinality of the difference between two HyperLogLogs combining the merge and count operations.
The snowflake schema is represented by centralized fact tables which are connected to multiple dimensions. "Snowflaking" is a method of normalizing the dimension tables in a star schema . When it is completely normalized along all the dimension tables, the resultant structure resembles a snowflake with the fact table in the middle.
Snowflake IDs, or snowflakes, are a form of unique identifier used in distributed computing. The format was created by Twitter (now X) and is used for the IDs of tweets. [ 1 ] It is popularly believed that every snowflake has a unique structure, so they took the name "snowflake ID".
A Universally Unique Identifier (UUID) is a 128-bit label used to uniquely identify objects in computer systems. The term Globally Unique Identifier (GUID) is also used, mostly in Microsoft systems.
The major criterion to distinguish "snowflake" unique content from run-of-the-mill content is the "critical commentary" test: Has the item merited comments that suppose a value judgment or elaborate critique (i.e. information other than a routine description of its properties) by independent critics?
The star schema is an important special case of the snowflake schema, and is more effective for handling simpler queries. [2] The star schema gets its name from the physical model's [3] resemblance to a star shape with a fact table at its center and the dimension tables surrounding it representing the star's points.
Joining data from multiple sources (e.g., lookup, merge) and deduplicating the data; Aggregating (for example, rollup – summarizing multiple rows of data – total sales for each store, and for each region, etc.) Generating surrogate-key values; Transposing or pivoting (turning multiple columns into multiple rows or vice versa)
Cubes (OLAP server) is another lightweight open-source toolkit implementation of OLAP functionality in the Python programming language with built-in ROLAP. ClickHouse is a fairly new column-oriented DBMS focusing on fast processing and response times. DuckDB [32] is an in-process SQL OLAP [33] database management system.