https://dev.mysql.com/exists-and-not-exists-subqueries.html
For the preceding example, if t2 contains any rows, even rows with nothing but NULL values, the EXISTS condition is TRUE. If a subquery returns any rows at all, EXISTS subquery is TRUE, and NOT EXISTS subquery is FALSE. For example: SELECT column1 ...
https://dev.mysql.com/extensions-to-ansi.html
MySQL Server supports some extensions that you probably will not find in other SQL DBMSs. Be warned that if you use them, your code will not be portable to other SQL servers. For example, MySQL Server recognizes the STRAIGHT_JOIN keyword in the ...
https://dev.mysql.com/fulltext-boolean.html
MySQL can perform boolean full-text searches using the IN BOOLEAN MODE modifier. With this modifier, certain characters have special meaning at the beginning or end of words in the search string. In the following query, the + and - operators ...
https://dev.mysql.com/fulltext-stopwords.html
The stopword list is loaded and searched for full-text queries using the server character set and collation (the values of the character_set_server and collation_server system variables). False hits or misses might occur for stopword lookups if the ...
https://dev.mysql.com/function-optimization.html
A function is nondeterministic if, given fixed values for its arguments, it can return different results for different invocations. If a function is tagged nondeterministic, a reference to it in a WHERE clause is evaluated for every row (when ...
https://dev.mysql.com/general-thread-states.html
The following list describes thread State values that are associated with general query processing and not more specialized activities such as replication. Many of these are useful only for finding bugs in the server. After create This occurs when ...
https://dev.mysql.com/gis-class-geometry.html
Exterior, interior, and boundary of an empty geometry are not defined (that is, they are represented by a NULL value). It is a noninstantiable class but has a number of properties, described in the following list, that are common to all geometry ...
https://dev.mysql.com/group-replication-launching.html
It should show something like this: mysql> SHOW PLUGINS; +----------------------------+----------+--------------------+----------------------+-------------+ | Name | Status | Type | Library | License | ... Once server s1 has been configured and ...
https://dev.mysql.com/group-replication-requirements.html
Every table that is to be replicated by the group must have a defined primary key, or primary key equivalent where the equivalent is a non-null unique key. Server instances that you want to use for Group Replication must satisfy the following ...
https://dev.mysql.com/group-replication-secure-socket-layer-support-ssl.html
If this system variable is set to NULL when TLSv1.3 is used (which is the default if you do not set the system variable), the ciphersuites that are enabled by default are allowed, as listed in Section 6.3.2, “Encrypted Connection TLS Protocols and ... Group communication connections and distributed recovery connections can be secured using ...
