DEC Language Sensitive Editor (LSE) is available on the OpenVMS
platforms only.
LSE is an advanced text editor that is layered on DECTPU. SQL
supports two sets of LSE templates, one for interactive SQL and
one for module language. The templates guide you in entering
syntactically-correct statements.
NOTE
The LSE templates provided with Oracle Rdb only support SQL
syntax through V4.2. The templates do not provide support
for new and changed syntax after V4.2.
LSE templates are made up of placeholders representing SQL
syntax. You can expand a placeholder or token by positioning
the cursor anywhere on it and pressing CTRL/E. When you expand
the placeholders, LSE provides the required syntax or indicates
optional elements.
For more information about LSE, see the DEC Language Sensitive
Editor documentation.
For more information about other editors SQL supports, see the
online help topic EDIT.
1 – Invoking LSE
You can invoke LSE in either of the following two ways:
o To use LSE within interactive SQL, define the logical names
SQL$EDIT and LSE$ENVIRONMENT:
$ DEFINE SQL$EDIT LSE
$ DEFINE LSE$ENVIRONMENT -
_$ SYS$COMMON:[SYSLIB]LSE$SYSTEM_ENVIRONMENT.ENV
Then, when you enter the EDIT statement from within SQL, you
automatically invoke LSE with SQL templates.
o To invoke LSE from DCL level, type LSE followed by the name
of the file you want to edit. The file type determines
the templates that LSE uses. To invoke the templates for
interactive SQL, use the file type of SQL; to invoke the
templates for SQL module language, use the file type of
SQLMOD. For example, you can type the following commands:
$ LSE SAMPLE.SQL
or
$ LSE SAMPLE.SQLMOD
2 – General SQL Terms
You can access online help for any placeholder in the LSE
templates for SQL. To obtain this help while you are editing,
position your cursor on the placeholder, then press the PF1 and
PF2 keys in succession.
The templates include some placeholders for low-level syntax.
While these topics are essential to SQL, they are so general as
to not be applicable at top-level help. This topic, General_SQL_
Terms, serves as a location for the low-level help topics that
LSE requires.
2.1 – check_col_constraint
col-constraint=
---+---------------------------------++
+-> CONSTRAINT <constraint-name> -+|
+------------------------------------+
+-> PRIMARY KEY -----------------+
+-> UNIQUE ----------------------+
+-> NOT NULL --------------------+
+-> NULL ------------------------+
+-> CHECK (predicate) -----------+
+-> references-clause -----------+
+------------>-------------------+
+-------------<------------------+
+----+----------------------------+-->
+--> constraint-attributes --+
Specifies a predicate that column values inserted into the table
must satisfy.
2.2 – col_clause
A placeholder used in LSE templates for the DECLARE TABLE syntax.
The col-clause placeholder allows the optional expansions of
either the col-constraint or sql-and-dtr-clause placeholders.
In the following syntax diagram for col-definition, col-clause
is represented by the right-most syntax loop that includes col-
constraint and the sql-and-dtr-clause.
declare-col-definition =
--> <column-name> --> data-type -++------------------------++->
|+-> col-constraint ------+|
|+-> sql-and-dtr-clause --+|
+----------- <-------------+
See also the Help topic on col-definition, located at this same
level.
2.3 – column_qualifier
A placeholder used in LSE templates as an expansion of the
column-name placeholder. The templates use the term column-
qualifier to describe leftmost loop in the following syntax
diagram for the column-name syntax.
column-name =
---+----------->-----------------+-> <name-of-column> -->
+-> <table-name> -------+> . -+
+-> <view-name> --------+
+-> <correlation-name> -+
If you expand column-qualifier in the templates, you will see the
optional items of table-name, view-name, and alias.
2.4 – column_name
column-name =
---+----------->-----------------+-> <name-of-column> -->
+-> <table-name> -------+> . -+
+-> <view-name> --------+
+-> <correlation-name> -+
You can name columns in CREATE TABLE and ALTER TABLE statements.
In other SQL statements, the names you give to columns can be
qualified by table name, view names, or aliases.
The only time you must qualify column names is when they are
ambiguous. Joining a table with itself and joining two tables
with common column names are two cases that require qualified
column names.
You always have the option of qualifying column names. In complex
statements, such qualifiers often make the statements more
readable.
2.5 – col_definition
col-definition =
--> <column-name> --+
+---------------+
+---> column-type ---+--------------------------+-+--+
| +->DEFAULT value-expr | | |
| +->column-identity --------+ | |
+---> COMPUTED BY value-expr ---------------------+ |
+-------------------------<--------------------------+
+-+--------------------+----------------+
+-> col-constraint --+ |
+--------------------------<------------+
++------------------------+-----+-----------------------+->
+-> comment-is-clause --+ +-> sql-and-dtr-clause -+
The definition for a column in the table. SQL gives you two ways
to specify column definitions:
o By directly specifying a data type to associate with a column
name
o By naming a domain that indirectly specifies a data type to
associate with a column name
Either way also allows options of specifying column constraints
and formatting clauses.
2.6 – FILENAME
FILENAME is a keyword used in SQL syntax that is always followed
by a required file specification.
See the online help for file_spec, located at this same level,
for more information.
2.7 – file_spec
Specifies a valid file specification. A full file specification
includes:
o Network node name
o Device directory (on OpenVMS only)
o Directory name or list
o File name
o File type
o File version number (on OpenVMS only)
For example, on OpenVMS a full file specification is:
SPEEDY::YOURDISK:[YOURDIR]APPLICANTS.RDB;81
File specifications are used throughout SQL syntax. For
example, when you first create a database, you give the file
specifications for the database system files.
2.8 – integer
An integer is a whole number. It may be positive or negative,
depending on its use, but cannot have a fractional part.
SQL uses integers in many situations. For example, you specify an
integer to refer to columns by column number.
2.9 – n
Specifies an integer. For the GRANT statement, the integer
specifies the earliest relative position of the entry in the
ACL. For the EDIT statement, the integer tells SQL to save the
previous n statements.
2.10 – parameter
Parameters are a type of value expression. Many SQL clauses
that will not accept more general value expressions require
parameters.
A parameter is a variable declared in a host language program
that is associated with an SQL statement. The meaning of
parameter encompasses host variables named directly in embedded
SQL statements, actual and formal parameters in programs that
use SQL module language, and parameter markers in the statement
string of a PREPARE statement.
2.11 – path_or_file
Path-or-file is a placeholder used in LSE templates as an
expansion of the attach-clause, alter-database-clause and create-
database-clause placeholders.
You can expand the path-or-file placeholder to the syntax
FILENAME file-spec and PATHNAME path-name. See the online help
for FILENAME and path_name, located at this level, for more
information on those topics.
2.12 – path_name
A data dictionary path name can be:
o A full path name, such as CDD$TOP.MOLLY.SQL.PERSONNEL
o A relative path name
o A logical name for a full or relative path name
Unless you use the PATHNAME argument in the CREATE DATABASE
statement, SQL does not use the data dictionary to store data
definitions.
If you specify the PATHNAME argument when you first create a
database, SQL creates a path name that contains copies of data
definitions for the database.
2.13 – quoted_string
A quoted character string literal is a string of printable
characters enclosed in single quotation marks. The maximum length
of a character string is 1,024 octets. An unqualified character
string must contain characters only from the literal character
set of that session.
The printable ASCII characters consist of:
o Uppercase alphabetic characters:
A-Z
o Lowercase alphabetic characters:
a-z
o Numerals:
0-9
o Special characters:
! @ # $ % ^ & * ( ) - _ = + ` ~
[ ] { } ; : " \ | / ? > < . ,
For a list of the printable characters for MCS, see the OpenVMS
documentation; for a list of printable characters for the other
supported character sets, see the standard for that character
set.
2.14 – database_id
Database-id is a placeholder used in LSE templates. Database-id
expands to the placeholders ALIAS alias-name, FILENAME file-spec,
and PATHNAME path-name. See the online help for FILENAME and
path_name, located at this level, for more information. See the
Aliases HELP topic under the top-level topic User_Supplied_names
for more information on aliases.