FROM
<from_clause> | ::= |
FROM <from_entity> |
The FROM clause is used to specify the input format source(s) from which the query input records are to be read.
Remarks:
- The syntax and interpretation of the <from_entity> specified in the FROM clause depends on the input format used. For information on the syntax and interpretation of the <from_entity> values supported by each input format, refer to the Input Formats Reference.
-
Regardless of the input format used, the <from_entity> specified in the
FROM clause must comply with the following general syntax:
- The <from_entity> must be a single element or a list of elements,
separated by the ',' (comma) or ';' (semicolon) characters, as in the
following examples:
file1.txt file1.txt, file2.txt file1.txt; D:\file2.txt; file3.txt
- Each element can not contain spaces, ',' (comma) characters,
or ';' (semicolon) characters, unless the element is enclosed by the '''
(single quote) or '" (double quotes) characters, as in the following example:
file2.txt, 'C:\Program Files\file3.txt', file4.txt
- The following characters are considered parenthesys characters, and if
they appear in an element, they must appear as well-formed pairs of opening
and closing parenthesys:
< > ( ) [ ] { }
The following examples show valid from-entities containing parenthesys characters:
entity<value> entity[value]value
The following examples show invalid from-entities containing parenthesys characters:
entity>value< entity}value entity(value
- The <from_entity> must be a single element or a list of elements,
separated by the ',' (comma) or ';' (semicolon) characters, as in the
following examples:
-
Any character (including illegal characters and non-printable characters) in a
<from-entity> can be entered using the \uxxxx notation, where xxxx is the 4-digit hexadecimal
representation of the UNICODE character, as in the following example:
C:\Program\u0020Files\file3.txt
-
From-entities that represent names of files or directories are not allowed
to contain the following characters, even when enclosed in quote characters or entered
using the \uxxxx notation:
tab carriage-return line-feed , ( ) " < >
Examples:
A. <from_entity> with the REG input format
The following example query reads input records from the registry using the REG input format:SELECT * FROM \HKLM\SOFTWAREB. <from_entity> with the EVT input format
The following example query reads input records from the System and Security event logs using the EVT input format:SELECT * FROM System, Security
See also:
INTO
Basics of a Query
Input Formats Reference