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The use of square brackets [ ] indicates that something is optional, while a vertical line | indicates a choice shold be made between mutually exclusive options. Words in heavy mono-spaced type (e.g. SELECT) should be typed in literally .
SQL keywords are case insensitive.
Section Contents
select-statement :
SELECT select-list
FROM table-name
[ WHERE search-condition ]
[ ORDER BY sort-order ]
Use a select-statement to specify what data should be present in the view, and how to present it.
select-list :
*
column-name-comma-list
Specify * to request that all columns for the table be returned in the view, in an undefined order; otherwise a comma separated list specifies which columns to return, and the order that the columns appear in the view.
table-name
column-name
The table-name should be a table which exists in the database. Column names should refer to columns which exist in the specified table.
Section Contents
search-condition :
boolean-term [ OR search-condition ]
boolean-term :
boolean-factor [ AND boolean-term ]
boolean-factor :
[ NOT ] boolean-primary
boolean-primary :
predicate
( search-condition )
This specifies a condition which a row must meet to be present in the generated view. A trivial search condition is just a single predicate, more complex search conditions are constructed by combining predicates using the keywords AND, OR and NOT, and using parentheses to override the standard precedence of these operators. Without brackets, the order of precedence is NOT, AND then OR. e.g.
a=1 or not b=2 and c=3
is equivalent to
(a=1 or ((not b=2) and c=3))
predicate :
comparison-predicate
like-predicate
null-predicate
These are the building blocks of the search condition. Each predicate tests one condition of a column in the selected table.
comparison-predicate :
column-name comparison-operator literal
comparison-operator :
< | > | <= | >= | = | <>
Compare a column value with a supplied literal value. Numeric columns (including bit columns) are compared numerically, text columns are compared lexically and date columns are compared historically. Binary columns cannot be compared. The literal must be of the same type (numeric, string, date) as the column.
literal :
string-literal
numeric-literal
date-literal
A string-literal is a character string enclosed in single quote characters ‘. To include a single literal quote character ‘ in a string-literal, use two literal quote characters ‘’.
A numeric-literal is any sequence of characters which can be interpreted as a valid decimal integral or floating point number.
A date-literal is a character string enclosed by the # character, which can be interpreted as a valid date.
like-predicate :
column-name [ NOT ] LIKE pattern-value
pattern-value :
string-literal
Test whether or not a text column matches a pattern string. The wildcard characters used in the pattern-value are not standard SQL, instead the EPOC32 wildcard characters are used: ? for matching any single character and * for matching zero or more characters.
null-predicate :
column-name IS [ NOT ] NULL
Test whether or not a column is Null. This predicate can be applied to all column types.
sort-order :
sort-specification-comma-list
sort-specification :
column-name [ ASC | DESC ]
Without an ORDER BY clause in the select statement the order that rows are presented is undefined. The columns specified in the sort-order can be ordered in ascending (the default) or descending order, and should appear in the sort-order in decreasing order of precedence. e.g.
surname, first_name
will order the rows by the column surname, and any rows with identical surnames will then be ordered by the column first_name.
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