Static Table Characteristics-opracowanie

Static Table Characteristics
Static format is the default for MyISAM tables. It is used when the table contains no variable-length
columns (VARCHAR, VARBINARY, BLOB, or TEXT). Each row is stored using a fixed number of bytes.
Of the three MyISAM storage formats, static format is the simplest and most secure (least subject to
corruption). It is also the fastest of the on-disk formats due to the ease with which rows in the data file
can be found on disk: To look up a row based on a row number in the index, multiply the row number
by the row length to calculate the row position. Also, when scanning a table, it is very easy to read a
constant number of rows with each disk read operation.
The security is evidenced if your computer crashes while the MySQL server is writing to a fixed-format
MyISAM file. In this case, myisamchk can easily determine where each row starts and ends, so it can
usually reclaim all rows except the partially written one. Note that MyISAM table indexes can always be
reconstructed based on the data rows.
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