Horizontal and vertical segmentation in database __ Database

During the interview forget the table division of the relevant knowledge, the blind spot back up a bit.

1 Horizontal split: Places data rows into two separate tables based on the values of one or more columns of data.

2 Vertical Partitioning: Place the main code and some columns into a table, and then place the main code and other columns in the other table.

Vertical split: Split by column, which saves a record in multiple places, with the same number of rows per child table.

Horizontal split: Split by record, different records can be saved separately, each child table has the same number of columns.

Table hash: Similar to horizontal segmentation, but there is no obvious dividing line such as horizontal segmentation, it is determined by the hash function and the key value of a record to save the file, so that the IO more balanced.