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**OPT**

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The **OPT** attribute (PROP:OPT) excludes entries in the KEY or INDEX for records with "null" values in all fields comprising the KEY or INDEX. For the purpose of this attribute, a "null" value is defined as zero in a numeric field or all blank spaces (20h) in a string field.

**Example:**

**Names   FILE,DRIVER('Clarion'),PRE(Nam)  !Declare a file structure**

**NameKey  KEY(Nam:Name),****OPT****         !Declare name key, exclude blanks**

**NbrKey   KEY(Nam:Number),****OPT****       !Declare number key, exclude zeroes**

**Rec      RECORD**

**Name      STRING(20)**

**Number    SHORT**

**         END**

**        END**

**See Also:**

[[index  declare static file access index .htm|INDEX]]

[[key  declare dynamic file access index .htm|KEY]]