1z0-909 MySQL 8.0 Database Developer Questions and Answers

Secondary index access will always be faster than a table scan.

Indexing all of a table's columns improves performance.

Indexes contain rows sorted by key values.

Indexes reduce disk space used.

Indexes are used to enforce unique constraints.

product->''$.varieties [4]. origin[1];;

''$.varieties[4]. origin[1]''

product->varieties[3]. origin[0]''

''$.varieties [3]. origin[0]''

log_queries_not_using_indexes

log__slow_admin_statements=1

log_queries_not_using_indexes=ON

log_throttle_queries_not_using_indexes=100

The select requires json_unquoteo in the where clause.

The virtual values in the name column must be accessed using functions.

The JSON datatype cannot be used in virtual columns.

The json_extract() function requires a length value that matches the field length in the schema.

Table statistics must be updated to generate values for the name column.

It helps to store data items in a schema-less key-value store.

It can store documents greater than 4 GB.

It depends heavily on strictly typed data.

It allows one to bypass the SQL layer of the server.

There is no access to relational tables.

timestamp has larger range of values.

timestamp uses less storage space.

timestamp stores more decimal points in seconds

timestamp converts the value based on the session time zone.

timestamp stores the interval between two dates.