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The following is a short list of properties that are particularly targeted to the components of a FILE structure. See also [[runtime view and file properties.htm|Runtime FILE and VIEW Properties]] for a more comprehensive list.

__**Multi-File Properties**__

| [[file structure properties.htm#akfojuu|PROP:BINARY]] | [[file structure properties.htm#vzpepi|PROP:Dim]] | [[file structure properties.htm#dys38vu|PROP:Label]] |
| [[file structure properties.htm#propnamefile|PROP:NAME]] | [[file structure properties.htm#xm6kyy|PROP:Over]] | [[prop places.htm#z8cwzb|PROP:Places]] |
| [[file structure properties.htm#ahvus7l|PROP:Size]] | [[file structure properties.htm#ahx0i7l|PROP:Type]] |  |

__**File Properties**__

| [[file structure properties.htm#propblob|PROP:BLOB]] | [[file structure properties.htm#i4ysfu|PROP:Blobs]] | [[file structure properties.htm#alofjwa|PROP:CREATE]] |
| [[file structure properties.htm#amok4hn|PROP:Driver]] | [[file structure properties.htm#prop driverstring|PROP:DriverString]] | [[file structure properties.htm#lroww4|PROP:ENCRYPT]] |
| [[file structure properties.htm#p5h5yb|PROP:Fields]] | [[file structure properties.htm#pfdriver|PROP:FileDriver]] | [[file structure properties.htm#vzpllu|PROP:KEY]] |
| [[file structure properties.htm#cyntyla|PROP:Keys]] | [[file structure properties.htm#ahpqfb7|PROP:Memos]] | [[file structure properties.htm#vzppli|PROP:OEM]] |
| [[file structure properties.htm#ib9rit|PROP:OWNER]] | [[file structure properties.htm#dx7l0o1|PROP:RECLAIM]] | [[file structure properties.htm#prop pre|PROP:PRE]] |
| [[file structure properties.htm#gmoq061|PROP:THREAD]] |  |  |

__**Key Properties**__

| [[file structure properties.htm#acgcojg|PROP:Ascending]] | [[file structure properties.htm#s8z3l0|PROP:Components]] | [[file structure properties.htm#vzpf1l|PROP:DUP]] |
| [[file structure properties.htm#prop field2|PROP:FIELD]] | [[file structure properties.htm#p5h5yb|PROP:Fields]] | [[file structure properties.htm#awldjva|PROP:NOCASE]] |
| [[file structure properties.htm#vzppwp|PROP:OPT]] | [[file structure properties.htm#c0 m0x |PROP:PRIMARY]] |  |

The following properties are all elements of a FILE data structure. They describe the attributes, fields, keys, memos, and blobs that may occur within a FILE structure. All these FILE structure properties are READ ONLY except: PROP:NAME (which can be used to change the name of a field in a file), PROP:OWNER, and PROP:DriverString. Assigning values to these properties overrides any values in the relevant declared attributes

Some properties are specific to the FILE and take the label of the FILE structure as the //target//, others are specific to a KEY (or INDEX) and take the label of the KEY (or INDEX) as the //target//, and others are specific to a BLOB and take the label of the BLOB as the //target//. Several properties are arrays, which take the number of the specific field or key as their element number to identify which field or key to return.

Each field that appears within the RECORD structure receives a positve number. In the RECORD structure, field declarations begin with 1 and increment by 1 for each subsequent field, in the order in which they appear within the RECORD structure. Terminating END statements for GROUP structures are not numbered, as they are not a field declaration.

MEMO and BLOB fields are numbered negatively. MEMO and BLOB declarations begin with -1 and decrement by 1 for each subsequent MEMO and BLOB, in the order in which they appear within the FILE structure.

**See Also:** [[file structure properties example program .htm|File Structure Properties Example Program]]

__**Multi-Use File Structure Properties**__

**PROP:Label**

Returns the label of a declaration statement.

When no array element number is specified and the //target// is the label of a KEY (or INDEX), PROP:Label returns the label of the KEY (or INDEX).

When a positive array element number is specified and the //target// is a FILE, PROP:Label returns the label of the specified field within the RECORD structure.

When a negative array element number is specified and the //target// is a FILE, PROP:Label returns the label of the specified MEMO within the FILE structure.

When a positive array element number is specified and the //target// is a BLOB, PROP:Label returns the label of the specified BLOB.

**PROP:NAME**

The NAME attribute of the declaration statement.

When no array element number is specified and the //target// is the label of a FILE, PROP:Name returns the contents of the FILE statement's NAME attribute.

When a positive array element number is specified and the //target// is the label of a FILE, PROP:Name returns the NAME attribute of the specified field within the RECORD structure.

When a negative array element number is specified and the //target// is the label of a FILE, PROP:Name returns the NAME attribute of the specified MEMO or BLOB within the FILE structure.

When no array element number is specified and the //target// is the label of a KEY (or INDEX), PROP:Name returns the NAME attribute of the specified KEY (or INDEX).

**PROP:Size**

An array that returns the declared size of the specified MEMO, STRING, CSTRING, PSTRING, DECIMAL, or PDECIMAL field. The array index is the index of the field within the record structure.

file{PROP:Size, 1}  !returns the size of the first field in the file.

file{PROP:Size, -1} !returns the size of the first MEMO.

**PROP:Type**

The data type of the declaration statement.

When no array element number is specified and the //target// is the label of a KEY (or INDEX), PROP:Type returns either "KEY" or "INDEX."

When a positive array element number is specified and the //target// is the label of a FILE, PROP:Type returns a STRING that identifies the data type of the specified field within the RECORD structure.

PROP:Type now returns the type of the MEMO or BLOB. When a negative array element number is specified and the target is the label of a FILE, PROP:Type returns either "MEMO" or "BLOB"

__**FILE Statement Properties**__

These properties all take the label of a FILE as their //target//.

**PROP:BLOB**

Used with all database drivers that support the creation of BLOB columns:

**blobRef &= file{PROP:Blob, N}**

where //N// references the Blob Number to allocate (where a file may have multiple BLOBs)

This property is used to get a reference to a BLOB. //N// can be positive or negative. This will return a reference to the ABS(//N//)'th blob. Where //N// is the //n//'th memo or

blob. If //N// is a memo, NULL is returned.

Example:

**AFile ****FILE,DRIVER('TOPSPEED'),PRE(EMP)**

**M1 MEMO**

**B1 BLOB**

**RECORD**

**..**

**ABlob &BLOB**

**CODE**

**ABlob &= AFile{PROP:Blob, 1} !Returns NULL**

**ABlob &= AFile{PROP:Blob, -1}!Returns NULL**

**ABlob &= AFile{PROP:Blob, 2} !ABlob is a reference to AFile.B1**

**ABlob &= AFile{PROP:Blob, -2}!ABlob is a reference to AFile.B1**

**PROP:Blobs**

Returns the number of BLOB fields in the FILE structure.

**PROP:CREATE**

The CREATE attribute on the FILE statement. A toggle attribute which contains a null string ('') if absent, and '1' if present.

**PROP:DRIVER**

The DRIVER attribute. Returns the file driver of the FILE.

**PROP:DriverString**

A FILE property that returns the second parameter of the DRIVER() attribute of a file.

**PROP:ENCRYPT**

The ENCRYPT attribute on the FILE statement. A toggle attribute which contains a null string ('') if absent, and '1' if present.

**PROP:FileDriver**

Valid if you have the Dynamic File Driver system installed. You can now dynamically change the file driver of a statically defined file driver using

**filelabel{PROP:FileDriver} = ADDRESS(OtherFile)**.

A file with the THREAD attribute will need to have its driver changed every time a thread comes into existence.

**PROP:Key**

An array that returns a reference to the specified KEY or INDEX in the FILE structure. This reference can be used as the source side of a reference assignment statement.

**PROP:Keys**

Returns the number of KEY and INDEX declarations in the FILE structure.

**PROP:Memos**

Returns the number of MEMO fields in the FILE structure.

**PROP:OWNER**

The OWNER attribute on the FILE statement.

**PROP:OEM**

The OEM attribute on the FILE statement. A toggle attribute which contains a null string ('') if absent, and '1' if present.

**Prop:PRE**

A Write-Only property for use in the dynamic file system to let you set the prefix of a dynamic file. This makes it easier to create duplicates of existing files without having to put the prefix in the name of all the components of the file.

**PROP:RECLAIM**

The RECLAIM attribute on the FILE statement. A toggle attribute which contains a null string ('') if absent, and '1' if present.

**PROP:THREAD**

The THREAD attribute on the FILE statement. A toggle attribute which contains a null string ('') if absent, and '1' if present.

__**Key Properties**__

These properties all take the label of a KEY (or INDEX) as their //target//.

**PROP:Ascending**

An array that returns '1' if the specified key component is in ascending order, and a null string ('') if in descending order.

**PROP:Components**

Returns the number of component fields of a KEY or INDEX.

**PROP:DUP**

The DUP attribute on the KEY statement. A toggle attribute which contains a null string ('') if absent, and '1' if present.

**PROP:Field**

An array that returns the field number (within the RECORD structure) of the specified component field of a KEY or INDEX. This field number can be used as the array element number for PROP:Label or PROP:Name.

**PROP:NOCASE**

The NOCASE attribute on the KEY or INDEX statement. A toggle attribute which contains a null string ('') if absent, and '1' if present.

**PROP:OPT**

The OPT attribute on the KEY or INDEX statement. A toggle attribute which contains a null string ('') if absent, and '1' if present.

**PROP:PRIMARY**

The PRIMARY attribute on the KEY statement. A toggle attribute which contains a null string ('') if absent, and '1' if present.

__**Field Properties**__

The following properties all take the label of a FILE as their //target//.

**PROP:BINARY**

The BINARY attribute on the MEMO or BLOB statement in the FILE structure. A toggle attribute which contains a null string ('') if absent, and '1' if present.

**PROP:Dim**

An array property of a file that returns the product of the array dimensions specified in the DIM attribute of the specified field. For example, for a field DIM(3,2) PROP:Dim returns 6.

**PROP:Fields**

There are several forms of the PROP:Fields property:

//keylabel//{PROP:Fields}

Returns the number of fields in the key definition

//filelabel//{PROP:Fields}

Returns the number of fields declared in the RECORD structure.

//filelabel//{PROP:Fields, n}

Returns the number of fields in the group. The value of this property is only defined if //file//{PROP:Type, n} returns 'GROUP'.

//viewlabel//{PROP:Fields}

Returns the number of fields declared in a VIEW.

//viewlabel//{PROP:Fields, n}

Returns the number of fields projected for the //n// file. If //n// is 0 then the total number of projects in the view is returned.

Example:

**v VIEW(PFile),ORDER('PFile:String1'),FILTER('PFile:ID = 3')**

**   PROJECT(PFile:ID, PFile:String1)**

**    JOIN(Child1:Keyname, PFile:ID)         !File Child1 has 4 fields**

**     JOIN(Child2:Keyname, Child1:ID)       !File Child2 has 4 fields**

**      JOIN(Child3, 'Child3:LinkField = Child2:ID')**

**       PROJECT(Child3:String2)**

**      END**

**     END**

**     JOIN(Child2Child1:KeyName, Child1:ID) !File Child2Child1 has 4 fields**

**    END**

**   END**

**  END**

**v{PROP:Fields, 0}** will return 15

**v{PROP:Fields, 1}** will return 2

**v{PROP:Fields, 2}** will return 4

**v{PROP:Fields, 3}** will return 4

**v{PROP:Fields, 4}** will return 1

**v{PROP:Fields, 5}** will return 4

**See also:** [[join  declare a  join  operation .htm|JOIN]]

**PROP:Over**

An array property of a file that returns the field number of the field referenced in the OVER attribute on the specified field.