| = value |
Matches if the character string in, or the value
of, the data-record field equals the specified text or value. If you
specify a character string, the characters must be delimited by quotes.
For example, if you are matching on a field named City, the match
condition = "Dallas" selects all records whose City field
contains the entry Dallas. |
| value |
Equals (=) is the default operator. Thus, this
case is equivalent to = value, except that
the characters do not have to be delimited by quotes. For example,
if you are matching on a field named City, the match condition Dallas selects
all records whose City field contains the entry Dallas. |
| > value |
Matches if the data record field is greater than
the specified value. For example, if you are matching on a field named
Income, the match condition > 50000 selects all records
whose Income field contains an entry greater than 50,000. Character
strings must be delimited by quotes (> "Jones"). |
| < value |
Matches if the data record field is less than the
specified value. For example, if you are matching on a field named
Income, the match condition < 50000 selects all records
whose Income field contains an entry less than 50,000. Character
strings must be delimited by quotes (< "Jones"). |
| >= value |
Matches if the data-record field is equal to or
greater than the specified value. For example, if you are matching
on a field named Income, the match condition >= 50000 selects
all records whose Income field contains an entry of 50,000 or greater.
Character strings must be delimited by quotes (>= "Jones"). |
| <= value |
Matches if the data-record field is less than or
equal to the specified value. For example, if you are matching on
a field named Income, the match condition <= 50000 selects
all records whose Income field contains an entry of 50,000 or less.
Character strings must be delimited by quotes (<= "Jones"). |
| <> value |
Matches if the data-record field is not equal to
the specified value. Character strings must be delimited by quotes. For
example, if you are matching on a field named State, the match condition <>"TX" selects
all records whose State field contains an entry other than TX. |
| between value1 and value2 |
Matches if the data-record field is between the
range specified in value 1 and value 2. For example, if you are matching
on a field named Income, the match condition between 50000 and
100000 selects all records whose Income field contains an entry 50,000
- 100,000. Character strings must be delimited by quotes. |
| and |
Constructs a comparison of two or more items. Matches
only if the data record fields match all of the comparisons. The comparisons
can only be applied to one field. For example, if you are matching
a field named Income, the match condition > 5000 and <> 6000
selects all the records with income greater than 5000, but not a record
of 6000. |
| or |
Constructs a comparison of two or more items. Matches
if the data record fields match any of the comparisons. For example,
if you are matching on a field named City, the match condition = "Dallas" or
= "Fort Worth" selects all records whose City field contains
either the entry Dallas or the entry Fort Worth. |
| NULL |
Matches when all characters are blank or when a
character is binary zero (null). For example, you might want to discard
any records that have all blanks for a name field. |
| * (asterisk) |
Wildcard match of any number of characters in a
string. For example, to match on a field that contains the city name
and state, the match condition Dall* would select records
with any of the following entries:
- Dallas-Forth Worth
- Dallas, TX
- Dallas TX
|
| ? |
Matches any single character in a string. For
example, to match on a field that contains a last name, the match
condition Sm?th would select records with any of the following
entries:
|