How to read online help for SQL statements

Specific conventions are used to represent the syntax of SQL statements in DB-Access online help screens.

You can request online help for SQL statements in either of the following ways:
  • Highlight the New, Modify, or Use-editor options on the SQL menu and press CTRL-W.
  • Press CTRL-W while you are on the NEW or MODIFY screens of the SQL menu.

The form of the syntax diagrams that shows when you request online Help for SQL statements in DB-Access is different from the syntax diagrams in the IBM® Informix® Guide to SQL: Syntax.

The conventions and rules governing SQL statement syntax in DB-Access online help screens are described in the following list.
Any term in an SQL statement that is displayed in uppercase letters is a keyword. Type keywords exactly, disregarding case, as shown in the following example:
CREATE SYNONYM synonym-name

This syntax indicates you must type the keywords CREATE SYNONYM or create synonym without adding or deleting spaces or letters.

Substitute a value for any term that is displayed in lowercase letters. In the previous example, substitute a value for synonym-name.
( )
Type any parentheses as shown. They are part of the syntax of an SQL statement and are not special symbols.
[ ]
Do not type brackets as part of a statement. They surround any part of a statement that is optional. For example:

This syntax indicates that you can type either CREATE TABLE or CREATE TEMP TABLE.

The vertical bar indicates a choice among several options. For example:

This syntax indicates that you can enter either VANILLA, CHOCOLATE, or STRAWBERRY and that, if you enter CHOCOLATE, you can also enter MINT.

{ }
When you must choose only one of several options, the options are enclosed in braces and are separated by vertical bars. For example:

This syntax indicates that you must enter either GUAVA, MANGO, or PASSIONFRUIT, but you cannot enter more than one choice.

An ellipsis indicates that you can enter an indefinite number of additional items, such as the one immediately preceding the ellipsis. For example:

This syntax indicates that you can enter a series of existing column names after the first one.

The IBM Informix Guide to SQL: Syntax contains more detailed syntax diagrams and instructions for interpreting the diagram format that is used in the publication.

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