php - Should table names be prefixed with the database name and period when using MySQL/PDO? -

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the vast majority of queries i've seen have database name followed period before table name. example:

select * mydatabase.mytable;

however, seems work well:

select * mytable;

is there reason have mydatabase. before each table name?

i using mysql via pdo in php.

is there reason have mydatabase. before each table name

yes, if performing cross database query; accessing , joining tables different database. example below db1 , db2 different databases.

select t1.*,t2.some_column db1.table1 t1   inner join db2.table2 t2 on t1.some_id_column = t2.some_id_column;

but if accessing tables same database , running query against database no need specifying qualified name (db_name.schema_name.table_name)


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