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https://dev.mysql.com/gis-point-property-functions.html
Unless otherwise specified, functions in this section handle their arguments as follows: If any argument is NULL, the return value is NULL. A Point consists of X and Y coordinates, which may be obtained using the ST_X() and ST_Y() functions, ...
https://dev.mysql.com/group-replication-options.html
group_replication_recovery_public_key_path Property Value Command-Line Format --group-replication-recovery-public-key-path=file_name Introduced 8.0.4 System Variable group_replication_recovery_public_key_path Scope Global Dynamic Yes SET_VAR Hint ...
https://dev.mysql.com/index-extensions.html
Consider this table definition: CREATE TABLE t1 ( i1 INT NOT NULL DEFAULT 0, i2 INT NOT NULL DEFAULT 0, d DATE DEFAULT NULL, PRIMARY KEY (i1, i2), INDEX k_d (d) ) ENGINE = InnoDB; This table defines the primary key on columns (i1, i2). InnoDB ...
https://dev.mysql.com/information-schema-optimization.html
row *************************** id: 1 select_type: SIMPLE table: cs partitions: NULL type: const possible_keys: PRIMARY,name key: name key_len: 194 ref: const rows: 1 filtered: 100.00 Extra: Using index *************************** 2. row ...
https://dev.mysql.com/json-validation-functions.html
Both functions handle null or invalid input as follows: If at least one of the arguments is NULL, the function returns NULL. Beginning with MySQL 8.0.17, MySQL supports validation of JSON documents against JSON schemas conforming to Draft 4 of the ...
https://dev.mysql.com/key-column-usage-table.html
This table provides no information about functional key parts because they are expressions and the table provides information only about columns. The KEY_COLUMN_USAGE table has these columns: CONSTRAINT_CATALOG The name of the catalog to which the ...
https://dev.mysql.com/keywords.html
Certain keywords, such as SELECT, DELETE, or BIGINT, are reserved and require special treatment for use as identifiers such as table and column names. This may also be true for the names of built-in functions. Reserved words are permitted as ...
https://dev.mysql.com/loading-tables.html
For missing values (such as unknown sexes or death dates for animals that are still living), you can use NULL values. Suppose that Diane gets a new hamster named “Puffball.” You could add a new record using an INSERT statement like this: mysql> ...Suppose that your pet records can be described as shown ...
https://dev.mysql.com/multiple-column-indexes.html
MySQL can create composite indexes (that is, indexes on multiple columns). For certain data types, you can index a prefix of the column (see Section 8.3.5, “Column Indexes”). MySQL can use multiple-column indexes for queries that test all the ...
https://dev.mysql.com/mysql-cluster-limitations-transactions.html
A number of limitations exist in NDB Cluster with regard to the handling of transactions. The NDBCLUSTER storage engine supports only the READ COMMITTED transaction isolation level. To ensure that a given transaction reads only before or after ...
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Document created the 26/06/2006, last modified the 26/10/2018
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