Qualifiers are used within SQL statements to reference data structures, such as databases, tables, or columns. For example, typically a SELECT query contains references to some columns and at least one table.
Qualifiers can be composed by one or more identifiers, where the initial parts affect the context within which the final identifier is interpreted:
db_name.tbl_name.col_name
. If a qualifier is composed by more than one identifier, a dot (.) must be used as a separator. All identifiers can be quoted individually. Extra spacing (including new lines and tabs) is allowed.
All the following examples are valid:
If a table identifier is prefixed with a dot (.), the default database is assumed. This syntax is supported for ODBC compliance, but has no practical effect on MariaDB. These qualifiers are equivalent:
Since MariaDB 10.0, for DML statements, it is possible to specify a list of the partitions using the PARTITION clause. See Partition Pruning and Selection for details.
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https://mariadb.com/kb/en/identifier-qualifiers/