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|  |  | | //file//| |
|  | **SET** | ( | //file//,// key//| **)** |
|  |  | | //file//,// filepointer//| |
|  |  | | //key//| |
|  |  | | //key//,// key//| |
|  |  | | //key//,// keypointer//| |
|  |  | |// key//,// key//,// filepointer//| |
|  |  | |// view //| |
|  |  | |// view //,// number //| |

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| **SET** | Initializes sequential processing of a FILE or VIEW. |
| //file// | The label of a FILE declaration. This parameter specifies processing in the physical order in which records occur in the data file. |
| //key// | The label of a KEY or INDEX declaration. When used in the first parameter position, //key// specifies processing in the sort sequence of the KEY or INDEX. |
| //filepointer// | A numeric constant, variable, or expression for the value returned by the POINTER(file) procedure. |
| //keypointer// | A numeric constant, variable, or expression for the value returned by the POINTER(key) procedure. |
| //View// | The label of a VIEW. |
| //Number// | An integer constant, variable or expression that specifies the start position based on the first //number// of components of the ORDER attribute. If omitted, all ORDER attribute components are used. |

**SET** initializes sequential processing for a FILE or VIEW. SET does not get a record, but only sets up processing order and starting point for the following NEXT or PREVIOUS statements.

**FILE Usage**

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SET initializes sequential processing of a data file. The first parameter determines the order in which records are processed. The second and third parameters determine the starting point within the file. If the second and third parameters are omitted, processing begins at the beginning (or end) of the file.

| SET(//file//) | Specifies physical record order processing and positions to the beginning (SET...NEXT) or end (SET...PREVIOUS) of the file. |
| SET(//file,key//) | Specifies physical record order processing and positions to the first record which contains values matching the values in the component fields of the //key//. NOTE: This form is rarely used and is only useful if the file has been physically sorted in the //key// order. A common mistake is to use this form when SET(//key//,//key//) is the actual form desired. |
| SET(//file,filepointer//) | Specifies physical record order processing and positions to the //filepointer// record within the //file//. |
| SET(//key//) | Specifies keyed sequence processing and positions to the beginning (SET...NEXT) or end (SET...PREVIOUS) of the file in that sequence. |
| SET(//key,key//) | Specifies keyed sequence processing and positions to the first or last record which contains values matching the values in the component fields of the //key//. Both //key// parameters must be the same. |
| SET(//key,keypointer//) | Specifies keyed sequence processing and positions to the //keypointer// record within the //key//. |
| SET(//key//,//key//,//filepointer//) | Specifies keyed sequence processing and positions to a record which contains values matching the values in the component fields of the //key// at the exact record number specified by //filepointer//. Both //key// parameters must be the same. |

When //key// is the second parameter, processing begins at the first or last record containing values matching the values in all the component fields of the specified KEY or INDEX. If an exact match is found, NEXT will read the first matching record while PREVIOUS will read the last matching record. If no exact match is found, the record with the next greater value is read by NEXT, the record with next lesser value is read by PREVIOUS.

The values for //filepointer// and //keypointer// are dependent on the file driver. They could be a record number, the relative byte position within the file, or some other kind of "seek position" within the file. These parameters are used to begin processing at a specific record within the file.

For all file drivers, an attempt to SET past the end of the file will set the EOF procedure to true, and an attempt to SET before the beginning of the file will set the BOF procedure to true.

**VIEW Usage**

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SET sets sequential processing for the VIEW to the beginning or end of the set of records specified by the FILTER attribute, sorted by the ORDER attribute. The optional //number// parameter limits the SET to assume that the values in the first specified //number// of expressions in the ORDER attribute are fixed. The VIEW must be OPEN before the SET.

**Example:**

**ViewOrder  VIEW(Customer),FILTER('Hea:OrderTotal >= 500') |,ORDER('-Hea:OrderDate,Cus:Name')**

**            PROJECT(Cus:AcctNumber,Cus:Name)**

**            JOIN(Hea:AcctKey,Cus:AcctNumber)     !Join Header file**

**             PROJECT(Hea:OrderNumber,Hea:OrderTotal,Hea:OrderDate)**

**             JOIN(Dtl:OrderKey,Hea:OrderNumber)   !Join Detail file**

**              PROJECT(Det:Item,Det:Quantity)**

**              JOIN(Pro:ItemKey,Dtl:Item)      !Join Product file**

**               PROJECT(Pro:Description,Pro:Price)**

**              END**

**             END**

**            END**

**           END**

** CODE**

** DO OpenAllFiles**

**!Physical file order, beginning of file**

** ****SET****(Customer)**

** Cus:Name = 'Smith'**

**!Physical file order, first record where Name = 'Smith'**

** SET(Customer,Cus:NameKey)**

** SavePtr = POINTER(Customer)**

**!Physical file order, physical record number = SavePtr**

** SET(Customer,SavePtr)**

**!NameKey order, beginning of file (relative to the key)**

** SET(Cus:NameKey)**

** SavePtr = POINTER(Cus:NameKey)**

**!NameKey order, key-relative record number = SavePtr**

** SET(Cus:NameKey,SavePtr)**

** Cus:Name = 'Smith'**

**!NameKey order, first record where Name = 'Smith'**

** SET(Cus:NameKey,Cus:NameKey)**

**               **

** Cus:Name = 'Smith'**

** SavePtr = POINTER(Customer)**

**!NameKey order, Name = 'Smith' and rec number = SavePtr**

** SET(Cus:NameKey,Cus:NameKey,SavePtr)**

** OPEN(ViewOrder)   **

** SET(ViewOrder)                   !Top of record set in ORDER sequence **

** LOOP                             !Read all records in file**

**  NEXT(ViewOrder)                 !read a record sequentially**

**  IF ERRORCODE() THEN BREAK END**

**  !Process the order**

**  END**

** END**

** Hea:OrderDate = TODAY()-1        !Assign yesterday's date**

** SET(ViewOrder,1)                 !and process just yesterday's orders  **

** LOOP                             !Read all records in file**

**  NEXT(ViewOrder)                 !read a record sequentially**

**  IF ERRORCODE() THEN BREAK.**

**  !Process the order**

**  END**

** END**

**See Also:**

[[next  read next record in sequence .htm|NEXT]]

[[previous  read previous view record in sequence .htm|PREVIOUS]]

[[filter  set view filter expression .htm|FILTER]]

[[order  set view sort order expression .htm|ORDER]]

[[open  open a data structure .htm|OPEN]]

[[pointer  return last queue entry position .htm|POINTER(queue)]]

[[pointer  return relative record position .htm|POINTER]]

[[get  read a record or entry .htm|GET]]

[[reset  reset record sequence position .htm|RESET]]

[[position  return record sequence position .htm|POSITION]]

**SQL Related Topics:**

[[zerodate.htm|ZERODATE]]