Optimizing tables will clear out unnecessary settings and speed up your tables slightly, but there is little point in doing this more than once a month, or once a week for very high traffic MySQL servers. These commands can be done by using the CHECK, REPAIR and ANALYZE MySQL commands. rest of query) It tells the optimizer to do it in the order you've specified. The mysqlcheck program can also be used to check (-c/-m/-C), repair (-r) and analyze (-a) the tables in a database. To add a full-text search index to the students sample table, we can use the below MySQL command: 2 1 mysql>Alter table students ADD FULLTEXT (firstname, lastname) 2 mysql>Select. Since your query looks like all the other tables are more 'lookup' reference only, and your Surveys table is the critical root table, just change. Note that when writing this command you should not put a space in between the -p and your password. ![]() mysqlcheck -o database -u user -ppassword This program is called mysqlcheck and can be run like this. For small tables or queries that select a large portion of a table, it can be faster for MySQL to skip the index scan and scan the table directly. You can do this for every table in the database, but to save time MySQL comes with a command line script that will optimize all tables in a database. The MySQL optimizer will always try to pick the quickest way to get the data it needs, which sometimes means choosing a slightly counter-intuitive method. The filtering is being used to determine whether a specific row from the right (nullable) table should be matched up or not. This also has the effect of resetting any auto incrementing numbers to the highest value in the table. Note that, with LEFT JOINs, some filtering in the ON clause may make sense. The OPTIMIZE TABLE will defragment the data and reclaim any unused space. Variable length columns are VARCHAR, VARBINARY, BLOB, or TEXT. ![]() This can be used if you have a table with any variable length rows and you make lots of changes to the data in that table. You can optimize MySQL tables using the OPTIMIZE command.
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