The SAS FedSQL Language Reference uses the Backus-Naur Form (BNF). Specifically, it
uses the same syntax notation that is used by Jim Melton in SQL:1999
Understanding Relational Language Components.
The main difference
between traditional SAS syntax and the syntax that is used in the
SAS FedSQL language reference documentation is in how optional syntax
arguments are displayed. In the traditional SAS syntax, angle brackets
(< >) are used to denote optional syntax. In the FedSQL syntax,
square brackets ([ ]) are used to denote optional syntax and angle
brackets are used to denote non-terminal components.
The following symbols
are used in the FedSQL syntax.
::=
This symbol can be
interpreted as “consists of” or “is defined as”.
< >
Angle brackets identify
a non-terminal component , that is a syntax component that can be
further resolved into lower level syntax grammar.
[ ]
Square brackets identify
optional arguments. Any argument that is not enclosed in square brackets
is a required argument. Do not type the square brackets unless they
are preceded by a backward slash (\), which denotes that they are
literal.
{ }
Braces provide a method
to distinguish required multi-word arguments. Do not type the braces
unless they are preceded by a backward slash (\) which denotes that
they are literal.
|
A vertical bar indicates
that you can choose one value from a group. Values separated by bars
are mutually exclusive.
…
An ellipsis indicates
that the argument or group of arguments that follow the ellipsis can
be repeated any number of times. If the ellipsis and the following
arguments are enclosed in square brackets, they are optional.
\
A backward slash indicates
that next character is a literal.
The following examples
illustrate the syntax conventions that are described in this section.
These examples contain selected syntax elements, not the complete
syntax.
1CREATE TABLE 2 {table | _NULL_}
3 [\{OPTIONS SAS-table-option=value [… SAS-table-option=value]\}]
(4 <column–definition> 5 [, ...<column-definition> | <table-constraint>])
6| 7AS query-expression
;
<column-definition>::=
column data-type [<column–constraint>] [DEFAULT value]
[HAVING [FORMAT format] [INFORMAT informat] [LABEL='label']]
| 1 |
CREATE
TABLE is in uppercase bold because it is the name of
the statement.
|
| 2 |
table is
italics because it is an argument that you can supply.
|
| 3 |
The
braces are preceded by a backward slash indicating that the braces
are literal.
|
| 4 |
<column–definition>
is in angle brackets because it is a non-terminal argument that is
further resolved into lower level syntax grammar.
|
| 5 |
The
square brackets and ellipsis around the second instance of <column-definition>
indicates that it is optional and you can repeat this argument any
number of times separated by commas.
|
| 6 |
You
can supply a <column-definition> or AS query-expression but
not both.
|
| 7 |
AS
is in uppercase roman because it is a literal argument.
|