Search Results
https://dev.mysql.com/doc/refman/8.4/en/spatial-aggregate-functions.html
MySQL supports aggregate functions that perform a calculation on a set of values. For general information about these functions, see Section 14.19.1, “Aggregate Function Descriptions”. ST_Collect() can be used as a window function, as signified ...
https://dev.mysql.com/doc/refman/8.4/en/spatial-index-optimization.html
MySQL permits creation of SPATIAL indexes on NOT NULL geometry-valued columns (see Section 13.4.10, “Creating Spatial Indexes”). The optimizer checks the SRID attribute for indexed columns to determine which spatial reference system (SRS) to ...
https://dev.mysql.com/doc/refman/8.4/en/spatial-operator-functions.html
This function processes geometry collections by extracting all vertex points of all components of the collection, creating a MultiPoint value from them, and computing its convex hull. OpenGIS proposes a number of functions that can produce ...
https://dev.mysql.com/doc/refman/8.4/en/starting-server-troubleshooting.html
You can create a my.cnf file and specify startup options for the engines that you plan to use. This section provides troubleshooting suggestions for problems starting the server. For additional suggestions for Windows systems, see Section 2.3.4, ...
https://dev.mysql.com/doc/refman/8.4/en/statement-caching.html
Metadata changes occur for DDL statements such as those that create, drop, alter, rename, or truncate tables, or that analyze, optimize, or repair tables. For certain statements that a client might execute multiple times during a session, the ...
https://dev.mysql.com/doc/refman/8.4/en/statement-labels.html
[begin_label:] BEGIN [statement_list] END [end_label] [begin_label:] LOOP statement_list END LOOP [end_label] [begin_label:] REPEAT statement_list UNTIL search_condition END REPEAT [end_label] [begin_label:] WHILE search_condition DO statement_list ...
https://dev.mysql.com/doc/refman/8.4/en/static-format.html
Creating a table having such columns with an explicit ROW_FORMAT clause does not raise an error or warning; the format specification is ignored. It is used when the table contains no variable-length columns (VARCHAR, VARBINARY, BLOB, or TEXT). Of ...
https://dev.mysql.com/doc/refman/8.4/en/string-comparison-functions.html
For example, consider the following table and data: CREATE TABLE foo (bar VARCHAR(10)); INSERT INTO foo VALUES (NULL), (NULL); The query SELECT COUNT(*) FROM foo WHERE bar LIKE '%baz%'; returns 0. Table 14.13 String Comparison Functions and ...
https://dev.mysql.com/doc/refman/8.4/en/string-literals.html
A string is a sequence of bytes or characters, enclosed within either single quote (') or double quote (") characters. Examples: 'a string' "another string" Quoted strings placed next to each other are concatenated to a single string. The following ...
https://dev.mysql.com/doc/refman/8.4/en/telemetry-metrics-meters.html
For example, to update the frequency of the mysql.inno metrics: mysql>update performance_schema.setup_meters set FREQUENCY='30' where name = 'mysql.inno'; The maximum number of meter instruments which can be created is set by ...