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https://dev.mysql.com/doc/refman/8.4/en/optimizing-innodb-bulk-data-loading.html
For optimal performance when loading data into an InnoDB FULLTEXT index, follow this set of steps: Define a column FTS_DOC_ID at table creation time, of type BIGINT UNSIGNED NOT NULL, with a unique index named FTS_DOC_ID_INDEX. For example: CREATE ... These performance tips supplement the general guidelines for fast inserts in Section 10.2.5.1, “Optimizing INSERT ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-firewall-groups-table.html
The value is NULL, or a non-NULL account that has the format user_name@host_name: If the value is NULL, the firewall records allowlist rules for statements received from any account that is a member of the group. If the value is non-NULL, the ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-timing.html
If an enabled instrument is not timed, events produced by the instrument have NULL for the TIMER_START, TIMER_END, and TIMER_WAIT timer values. Events that have not yet completed have an END_EVENT_ID value of NULL. Events are collected by means of ...
https://dev.mysql.com/doc/refman/8.4/en/rename-table.html
row *************************** Table: t3 Create Table: CREATE TABLE `t3` ( `i1` int(11) DEFAULT NULL, `i2` int(11) DEFAULT NULL, CONSTRAINT `t3_chk_1` CHECK ((`i1` > 0)), CONSTRAINT `t3_chk_2` CHECK ((`i2` < 0)) ) ENGINE=InnoDB DEFAULT ... RENAME ...
https://dev.mysql.com/doc/refman/8.4/en/spatial-type-overview.html
MySQL has spatial data types that correspond to OpenGIS classes. The basis for these types is described in Section 13.4.2, “The OpenGIS Geometry Model”. Some spatial data types hold single geometry values: GEOMETRY POINT LINESTRING POLYGON ...
https://dev.mysql.com/doc/refman/8.4/en/static-format.html
NULL columns require additional space in the row to record whether their values are NULL. Each NULL column takes one bit extra, rounded up to the nearest byte. The expected row length in bytes for static-sized rows is calculated using the following ...It is used when the table contains no variable-length columns (VARCHAR, VARBINARY, BLOB, or ...
https://dev.mysql.com/doc/refman/8.4/en/sys-ps-trace-thread.html
Use NULL to collect data for the default of 60 seconds. Dumps all Performance Schema data for an instrumented thread to a .dot formatted graph file (for the DOT graph description language). Each result set returned from the procedure should be used ...
https://dev.mysql.com/doc/refman/8.4/en/using-innodb-tables.html
row *************************** Name: t1 Engine: InnoDB Version: 10 Row_format: Dynamic Rows: 0 Avg_row_length: 0 Data_length: 16384 Max_data_length: 0 Index_length: 0 Data_free: 0 Auto_increment: NULL Create_time: 2021-02-18 12:18:28 Update_time: ... InnoDB tables are created using the CREATE TABLE statement; for example: CREATE TABLE t1 (a INT, b CHAR (20), PRIMARY KEY (a)) ENGINE=InnoDB; The ENGINE=InnoDB clause is not required when InnoDB is defined as the default storage engine, which it is by ...
https://dev.mysql.com/doc/c-api/8.4/en/mysql-library-init.html
#include <mysql.h> #include <stdlib.h> int main(void) { if (mysql_library_init(0, NULL, NULL)) { fprintf(stderr, "could not initialize MySQL client library\n"); exit(1); } /* Use any MySQL API functions here */ mysql_library_end(); return ... int ...
https://dev.mysql.com/doc/extending-mysql/8.4/en/adding-native-function.html
This function should also set maybe_null = 0 if the main function cannot return a NULL value. The function can check whether any of the function arguments can return NULL by checking the arguments' maybe_null variable. If you want to return NULL ...