Boolean operators

Boolean operators allow terms to be combined through logic operators.

Lucene supports the following Boolean operators:

AND && + OR || NOT ! -

Attention: The Lucene Boolean operators AND, OR, and NOT are case sensitive and must be written as shown.

AND

&&

The AND operator associates two terms or phrases and finds a matching record if both terms or phrases exist in a record. This is equivalent to the intersection of two sets. You can use the symbol && in place of the word AND.

Examples:

To search for records that contain both the word Beta1 and the phrase Beta2 test, use the following query:
```
Beta1 AND "Beta2 test"
```
To search for records that contain the word Beta1, the phrase Beta2 test, and 7.1, use the following query:
```
Beta1 AND "Beta2 test" AND 7.1
```
The following query returns the same results:
```
Beta1 && "Beta2 test" AND 7.1
```

+

The + operator, also known as the required operator, indicates that the term or phrase after the + operator exists somewhere in a field of a record.

Example:

To search for records that must contain the word Beta1 and might contain Beta2, use the following query:
```
+Beta1 Beta2
```

OR

||

The OR operator associates two terms or phrases and finds a matching record if either of the terms or phrases exists in a record. This is equivalent to the union of two sets. You can use the symbol || in place of the word OR.

Example:

To search for records that contain either the word Beta1 or the phrase Beta2 test, use the following query:
```
Beta1 OR "Beta2 test"
```
The following query returns the same results:
```
Beta1 || "Beta2 test"
```

NOT

The NOT operator excludes records that contain the term or phrase following the NOT operator. This is equivalent to a difference in sets.

Example:

To search for records that contain the word Beta1 but not Beta2, use the following query:
```
Beta1 NOT Beta2
```

Attention: The NOT operator cannot be used with just one term or phrase. For example, the following search will return no results: NOT Beta1

-

!

The - operator, also known as the prohibit operator, excludes records that contain the term or phrase after the symbol -. You can use the symbol ! in place of the operator -.

Example:

To search for records that contain the word Beta1 but not Beta2, use the following query:
```
Beta1 -Beta2
```
The following queries return the same results:
```
-Beta2 Beta1
```
```
!Beta2 Beta1
```