Comprehensive exposure to SQL syntax (3)

ORDER BY conditional statement

This conditional clause is usually used in conjunction with the SELECT statement to sort the query results according to the specified field.


SELECT fieldlist


FROM table


WHERE selectcriteria


ORDER BY field[ASC|DESC][,field2 [ASC|DESC][,...]]


　fieldlist

　The name of the field to be queried. Which can be used with ALL, DISTINCT, DISINCTROW, or TOP.


table


The name of the table to be queried.


　selectcriteria


　Query standard settings.


　field1

Specify which field to use as the basis for sorting. If you do not add ORDER BY, the data set queried will not be sorted.

　ASC

　Ascending order categories. (Default)


DESC

Categories in descending order.

For example:

Or if we want to arrange the output data according to the order of birth, we can use the following command.


　SELECT Name, Birthday

　FROM Staff Form


　ORDER BY Birthday

　SELECT LastName,FirstName

　FROM Employees

　ORDER BY LastName ASC;

　IN Conditional Clause

　Specify which table of the external database to be selected. (Must be a database that the Microsoft Jet database engine can connect to, such as dBase, Paradox, etc.)

　
SELECT|INSERT]INTO destination IN
{path|["path" "type"]| [""[type;DATABASE=path]]}
FROM tableexPRession IN
{path|["path" "type"]|[""[type;DATABASE=path]]}
destination


The name of the external table into which data is to be inserted.

　tableexpression

　Table name or the name of the table from which data is read. This parameter can be a single table name, or a stored SQL query, etc.

path

Contains the full path name of the table.

Type

The type name of the database, usually used when the database belongs to Jet database. (For example: dBASE III, dBASE IV, Paradox 3.x, Paradox 4.x, or Btrieve)

For example: the following two paragraphs have the same meaning


PartA... .FROM Table
IN ""[dBASE IV;DATABASE=C:DBASEDATASALES;];

PartB....FROM Table
IN "C:DBASEDATASALES" "dBASE IV;"



　For example: Microsoft Jet database


SELECT customer number
FROM customer form
IN CUSTOMER.MDB
WHERE customer number Like "A*";
Where CUSTOMER.MDBO is the database name of Jet database, which contains the customer table.

For example: dBASE III or IV
SELECT customer number
FROM customer form
IN "C:DBASEDATASALES" "dBASE IV;"
WHERE customer number Like "A*";
So when we use a database different from access, we must specify the type name of the database.

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