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ASK STRUCTURE struc_name: EXTRACTED num_var
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| Example 15-37 ASK STRUCTURE: EXTRACTED |
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open structure cl: name 'sheerpower:samples\client' extract structure cl end extract ask structure cl: extracted z print 'Records found: '; z end Records found: 13 |
ASK STRUCTURE: EXTRACTED asks the operating system for the last extracted count for the structure specified.
ASK STRUCTURE struc_name: ID str_var
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| Example 15-38 ASK STRUCTURE: ID |
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declare structure str
open structure cl: name 'sheerpower:samples\client'
ask structure cl: id cl_id$
set structure str: id cl_id$
extract structure str
end extract
for each str
print str(#1); ' '; str(#2)
next str
end
20000 Smith
20001 Jones
20002 Kent
23422 Johnson
32001 Waters
43223 Errant
80542 Brock
80543 Cass
80544 Porter
80561 Derringer
80573 Farmer
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The ASK STRUCTURE: ID statement asks the operating system for the ID of a structure and returns it in the string variable str_var.
ASK STRUCTURE struc_name: POINTER num_var
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| Example 15-39 ASK STRUCTURE: POINTER |
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open structure cl: name 'sheerpower:samples\client'
extract structure cl
end extract
for each cl
ask structure cl: pointer ptr
print ptr, cl(last)
next cl
end
1 Smith
2 Jones
3 Kent
4 Johnson
5 Waters
6 Errant
7 Brock
8 Cass
9 Porter
10 Derringer
11 Farmer
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From within a FOR EACH...NEXT STRUCTURE_NAME block, ASK STRUCTURE: POINTER asks the structure for the number of the current record pointer.
15.8.10 ASK STRUCTURE: RECORDSIZE
ASK STRUCTURE struc_name: RECORDSIZE int_var
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| Example 15-40 ASK STRUCTURE: RECORDSIZE |
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open structure cl: name 'sheerpower:samples\client' ask structure cl: recordsize recsize print 'Logical recordsize: '; recsize end Logical recordsize: 400 |
The ASK STRUCTURE: RECORDSIZE statement returns the record size of the structure data file.
ASK STRUCTURE struc_name: ACCESS str_var
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| Example 15-41 ASK STRUCTURE: ACCESS |
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open structure inv: name 'sheerpower:samples\invoice', access input ask structure inv: access x$ print x$ close structure inv end SECURITY:N, READ:N, WRITE:N, UPDATE:N, DELETE:N |
The ASK STRUCTURE: ACCESS statement retrieves the access rules for the specified structure. Security level, data file read, write, update, and delete rules are returned.
15.8.12 ASK | SET STRUCTURE #string_expr . . .
ASK STRUCTURE #string_expr. . .
SET STRUCTURE #string_expr. . .
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| Example 15-42 ASK | SET STRUCTURE#string_expr . . . |
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open structure cl: name 'sheerpower:samples\client'
str$ = 'CL'
fld$ = 'ID'
do_work
stop
routine do_work
ask structure #str$, field #fld$: description dsc$
print 'Description is: '; dsc$
end routine
end
Description is: Client ID number
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A string expression for the structure name can be used in an ASK STRUCTURE #string_expr or SET STRUCTURE #string_expr statement. This allows generalized code to be written to work for several structures.
ASK STRUCTURE struc_name : ENGINE str_var
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| Example 15-43 ASK STRUCTURE: ENGINE |
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open structure cl : name 'sheerpower:samples\vendor' ask structure cl : engine ename$ print 'DATABASE ENGINE is: '; ename$ end DATABASE ENGINE is: ARS |
The ASK STRUCTURE: ENGINE statement returns the name of the database engine (record management system) being used for the specified structure in str_var.
The SET STRUCTURE statement is used to change various device and structure characteristics from within your programs.
SET STRUCTURE struc_name: struc_option [num_var | str_var]
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SET STRUCTURE struc_name: CURRENT str_expr
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| Example 15-44 SET STRUCTURE: CURRENT |
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dim a$(100)
let i = 0
open structure cl: name 'sheerpower:samples\client'
extract structure cl
end extract
for each cl
print cl(last); ', '; cl(first)
input 'Would you like to see this record (Y/N)': yn$
if yn$ = 'Y' then
let i = i + 1
ask structure cl: current a$(i)
end if
next cl
print
for j = 1 to i
set structure cl: current a$(j)
print cl(last); ','; cl(first), cl(state), cl(phone)
next j
end
Errant, Earl Would you like to see this record (Y/N)? Y
Abott, Al Would you like to see this record (Y/N)? Y
Brock, Bud Would you like to see this record (Y/N)? N
Cass, Cathy Would you like to see this record (Y/N)? N
Derringer, Dale Would you like to see this record (Y/N)? Y
Farmer, Fred Would you like to see this record (Y/N)? Y
Errant, Earl CA (408) 844-7676
Abott, Al NY (202) 566-9892
Derringer, Dale CA (818) 223-9014
Farmer, Fred FL (305) 552-7872
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The CURRENT option sets the current record to that specified by the str_expr. The str_expr contains the information for the current record for the record management system being used. ASK STRUCTURE: CURRENT is used to store a current record value into a string variable.
When SheerPower executes a SET STRUCTURE: CURRENT statement, it uses the structure name and sets the current record to the value specified by the string variable. The structure must be open and str_expr must contain a value stored with the ASK STRUCTURE: CURRENT statement.
If a null string is used for the value, SheerPower sets the structure to no current record and sets _EXTRACTED to zero.
SET STRUCTURE struc_name: CURRENT ''
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15.9.2 SET STRUCTURE, FIELD: KEY
SET STRUCTURE struc_name, FIELD field_expr: KEY str_expr
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| Example 15-45 SET STRUCTURE, FIELD: KEY |
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open structure cl: name 'sheerpower:samples\client'
line input 'Enter an ID': id$
set structure cl, field id: key id$
if _extracted = 0 then
message error: 'Not found'
else
print cl(id), cl(last)
end if
end
Enter an ID? 80561
80561 Derringer
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