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Databases are structured data that is organized and stored, this could be anything from transactions, financials, customer data, or anything that is information worth storing. To run these databases algorithms written in different programming languages are used, they are at their very core procedures will all the necessary steps that define a set of instructions to be executed with a specific order in mind to get a desired output. For database analysis linking data is key, so there are a few important join algorithms created specifically for this they are, nested loops, sort/merge, hybrid, hash, and star.

The join process concept is the connection of a single loop, in the nested loop join the procedure gets a row from the outer table and searches for the row in the inner table this is commonly used when you need to repeat some action on the data. Sort merge uses two tables that are already sorted, they commonly use an index when this join occurs the algorithm is sorting relations by doing a sequential scan from one database to another.

A common use for the sort/merge algorithm is using large data sets that contain inequalities. When a hybrid join is used it is the culmination of the two prior join algorithms discussed, this is used when the outer table is sorted or where a join column index is used as well as the inner table must have an index on the join column. A hash join is when two tables have a hash file that is built and the search occurs on the hash value that is distributed in the join attributes, the hash function provides these hash values. The hash join is used when tables are not already sorted on the join column, so the optimizer builds an in-memory hash table on the inner table's join column, then the outer table is scanned for matches and joins the data from the two tables.

Using a star join algorithm allows multiple tables where there is a child table related to multiple parent tables in a one-to-many relationship using a bitmap join index. Therefore, a star join is a set of joins that is applied to a large central table in two or more dimensions (Mannino 2003, p.291). All these concepts are tough to fully grasp, as James 1:2 says, "Consider it all joy, my brethren, when you encounter various trials" (ESV), we need to keep trying no matter what trials we may be facing.