![]() Now we have an alias for departments table called d as well as the alias for the employees table called e. ORDER BY e.last_name DESC, d.department_name ASC SELECT e.employee_id, e.last_name, d.department_name Let us create one more table, which we will use in our exercises in subsequent chapters. Insert, Update, and Delete Records in a Temporary Table in SQLite Temporary tables can be incredibly useful in SQLite. You can choose to create aliases on any or all of the tables.įor example, we could modify our example above and create an alias for the departments table as well. When creating table aliases, it is not necessary to create aliases for all of the tables listed in the FROM clause. Now within this SQL statement, we can refer to the employees table as e. In SQLAlchemy, the database table is ultimately represented by a Python object similarly named Table. In this example, we've created an alias for the employees table called e. When we work with a relational database, the basic data-holding structure in the database which we query from is known as a table. ORDER BY e.last_name DESC, partment_name ASC schema tablename Thank you 10 3.7 (10 Votes) 0 3. schema tablename Thank you 10 0 0 3.7 10 Valora 105 points. Let's look at an example of how to alias a table name in SQLite.įor example: SELECT e.employee_id, e.last_name, partment_name sqlite describe table Code Example Octo7:04 AM / SQL sqlite describe table Savonne pragma tableinfo ('albums') View another examples Add Own solution Log in, to leave a comment 0 10 Azita 90 points describe sqlite. When you create an alias on a table, it is either because you plan to list the same table name more than once in the FROM clause (ie: self join), or you want to shorten the table name to make the SQL statement shorter and easier to read. The SQL standard way, as shown here: select columnname, datatype, charactermaximumlength, columndefault, isnullable from INFORMATIONSCHEMA.COLUMNS where tablename '' It's supported by many db engines.Since there are spaces in this alias_name, "largest ID" must be enclosed in quotes. In this example, we've aliased the MAX(employee_id) field as "largest ID". Next, let's look at an example where we are required to enclose the alias_name in quotes.įor example: SELECT department_id, MAX(employee_id) AS "largest ID" However, it would have been perfectly acceptable to write this example using quotes as follows: SELECT department_id, MAX(employee_id) AS "largest" Because our alias_name did not include any spaces, we are not required to enclose the alias_name in quotes. Parameters: tablename required: Name of attribute table drivername: Name of database driver: Options: dbf, odbc, ogr, pg, sqlite: Default: sqlite. ![]() As a result, largest will display as the heading for the second column when the result set is returned. In this example, we've aliased the MAX(employee) field as largest. For example, when using the MAX function, you might alias the result of the MAX function in SQLite.įor example: SELECT department_id, MAX(employee_id) AS largest ![]() Generally, aliases are used to make the column headings in your result set easier to read.
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