PDF (US Ltr)
- 35.1Mb
PDF (A4)
- 35.2Mb
Man Pages (TGZ)
- 256.4Kb
Man Pages (Zip)
- 361.2Kb
Info (Gzip)
- 3.4Mb
Info (Zip)
- 3.4Mb
Search Results
https://dev.mysql.com/doc/refman/5.7/en/json.html
(When the server is manipulating a JSON value internally in memory, it can be larger than this; the limit applies when the server stores it.) A JSON column cannot have a non-NULL default value. A path that does not exist in the document (evaluates ...The JSON data type provides these advantages over storing JSON-format strings in a string column: Automatic validation of JSON documents stored in JSON ...
https://dev.mysql.com/doc/refman/5.7/en/mysql-cluster-programs-ndb-desc.html
ndb_desc provides a detailed description of one or more NDB tables. Usage ndb_desc -c connection_string tbl_name -d db_name [options] ndb_desc -c connection_string index_name -d db_name -t tbl_name Additional options that can be used with ndb_desc ...
https://dev.mysql.com/doc/refman/5.7/en/innodb-information-schema-metrics-table.html
Because no DML operations have been performed, the counter values are zero or NULL. row *************************** NAME: dml_inserts SUBSYSTEM: dml COUNT: 0 MAX_COUNT: 0 MIN_COUNT: NULL AVG_COUNT: 0 COUNT_RESET: 0 MAX_COUNT_RESET: 0 ... The ...
https://dev.mysql.com/doc/refman/5.7/en/group-by-modifiers.html
These rows have the country and products columns set to NULL. This row has the year, country, and products columns set to NULL. The NULL indicators in each super-aggregate row are produced when the row is sent to the client. For any column in the ...
https://dev.mysql.com/doc/refman/5.7/en/json-modification-functions.html
All members of the second object which do not have a corresponding key in the first object, and whose value is not the JSON null literal. All members with a key that exists in both the first and the second object, and whose value in the second ...
https://dev.mysql.com/doc/refman/5.7/en/create-table-foreign-keys.html
SET NULL: Delete or update the row from the parent table and set the foreign key column or columns in the child table to NULL. Both ON DELETE SET NULL and ON UPDATE SET NULL clauses are supported. If you specify a SET NULL action, make sure that you ... MySQL supports foreign keys, which permit cross-referencing related data across tables, and foreign key constraints, which help keep the related data ...
https://dev.mysql.com/doc/refman/5.7/en/ansi-diff-foreign-keys.html
If ON UPDATE CASCADE or ON UPDATE SET NULL recurses to update the same table it has previously updated during the same cascade, it acts like RESTRICT. This means that you cannot use self-referential ON UPDATE CASCADE or ON UPDATE SET NULL operations. A self-referential ON DELETE SET NULL, on the other hand, is possible, as is a self-referential ON DELETE ...For example, if you define a RESTRICT type constraint, ...
https://dev.mysql.com/doc/refman/5.7/en/create-index.html
A UNIQUE index permits multiple NULL values for columns that can contain NULL. Otherwise, _rowid refers to the column in the first UNIQUE NOT NULL index if that index consists of a single integer column. If the first UNIQUE NOT NULL index does not ... CREATE [UNIQUE | FULLTEXT | SPATIAL] INDEX index_name [index_type] ON tbl_name (key_part,...) [index_option] [algorithm_option | lock_option] ...
https://dev.mysql.com/doc/refman/5.7/en/information-schema-optimization.html
row *************************** id: 1 select_type: SIMPLE table: VIEWS type: ALL possible_keys: NULL key: TABLE_SCHEMA,TABLE_NAME key_len: NULL ref: NULL rows: NULL Extra: Using where; Open_frm_only; Scanned 0 databases Use of constant database and ... Applications that monitor databases may make frequent use of INFORMATION_SCHEMA ...
https://dev.mysql.com/doc/refman/5.7/en/logical-operators.html
Table 12.5 Logical Operators Name Description AND, && Logical AND NOT, ! Negates value OR, || Logical OR XOR Logical XOR In SQL, all logical operators evaluate to TRUE, FALSE, or NULL (UNKNOWN). In MySQL, these are implemented as 1 (TRUE), 0 ...