Need to return to same form after query returns 0 recs

[Wanda Tucker]

But - hey! The darned thing works, now - do I want to fix what 'ain't broken? My daddy always said NO.

Okay - if you insist...here is the final code that works:

'Date Created: 23-May-2006 10:40:48 AM
'Last Updated: 24-May-2006 08:34:36 AM
'Created By : tuckerw
'Updated By : tuckerw
'Are there matching records present in the table?
dim global tbl as P
dim global qry as P
dim global nrecs as N

tbl = table.open("sites")

query.description = "Search for matching records"
query.order = ""
query.filter = "trim(Sites->Equake)=\"Y\""
query.options = ""
nrecs= a5_get_records_in_query("sites","equake=\"Y\"")

IF (nrecs = 0) then
qry.drop()
ui_msg_box("Null Query","There are no matching records in this search, unable to proceed" ,UI_INFORMATION_SYMBOL)
tbl.close()
end 'If there are no matching records, script ends here

else
'Close Quick Screen
DIM mode as c
mode = parentform.mode_get()
'If the form is in Enter or Change mode, first save the changes before closing the form
if mode = "ENTER" .or. mode = "CHANGE" then
parentform.commit()
'Check to see if the record was successfully saved
if parentform.mode_get()<>"VIEW" then
ui_msg_box("Unable to save your changes","Please correct and save, or discard your changes", UI_STOP_SYMBOL)
end
end if
end if
'Close the form
parentform.close(.f.)

'Opens sites and runs saved query on Equate
query.filter = "trim(Sites->Equake)=\"Y\""
query.order = ""


'Open the layout_type showing just the records that satisfy the filter
DIM Shared varP_Sites as P
DIM layout_name as c
layout_name = "Sites"


dim tempP as p
'Get pointer to existing window. In case layout_name is qualified with a dictionary name, extract up to first @. In case formname has spaces, normalize it
tempP=obj(":"+object_name_normalize(word(layout_name,1,"@")))
'Test if pointer is valid
if is_object(tempP) then
'Test if pointer refers to a form or browse
if tempP.class() = "form" .or. tempP.class() = "browse" then
'Apply the query to the form or browse as the Base query. (this means that
'the user cannot turn the query off, only add to the query)
tempP.BaseQueryRun(query.filter,query.order)
'then activate the already open window
tempP.activate()
else
'Window is not already open, so open it
varP_Sites = :Form.viewqueried(layout_name,query.filter, query.order )

end if
else
varP_Sites_Plus = :Form.viewqueried(layout_name,query.filter, query.order )

end if
xbasic_wait_for_idle()
tbl.close()
end if

Now, if someone can figure out how to "nest" the queries - I'd be elated...

Thank you,
Wanda

[Stan Mathews]

You can leave it alone (no harm anywhere) or you can use the code below. Lines shown in red with '--------------- can be deleted because nrecs= a5_get_records_in_query("sites","equake=\"Y\"") does all that.

'Date Created: 23-May-2006 10:40:48 AM
'Last Updated: 24-May-2006 08:34:36 AM
'Created By : tuckerw
'Updated By : tuckerw
'Are there matching records present in the table?
[COLOR="red"]'--------------dim global tbl as P
'--------------dim global qry as P[/COLOR]
dim global nrecs as N

[COLOR="Red"]'----------tbl = table.open("sites")[/COLOR]

[COLOR="red"]'----------query.description = "Search for matching records"[/COLOR]
[COLOR="red"]'----------query.order = ""[/COLOR]
[COLOR="red"]'----------query.filter = "trim(Sites->Equake)=\"Y\""[/COLOR]
[COLOR="red"]'----------query.options = ""[/COLOR]
nrecs= a5_get_records_in_query("sites","equake=\"Y\"")

IF (nrecs = 0) then
[COLOR="red"]'----------qry.drop()[/COLOR]
ui_msg_box("Null Query","There are no matching records in this search, unable to proceed" ,UI_INFORMATION_SYMBOL)
[COLOR="red"]'----------tbl.close()[/COLOR]
end 'If there are no matching records, script ends here

else
'Close Quick Screen
DIM mode as c
mode = parentform.mode_get()
'If the form is in Enter or Change mode, first save the changes before closing the form
if mode = "ENTER" .or. mode = "CHANGE" then
parentform.commit()
'Check to see if the record was successfully saved
if parentform.mode_get()<>"VIEW" then
ui_msg_box("Unable to save your changes","Please correct and save, or discard your changes", UI_STOP_SYMBOL)
end
end if
end if
'Close the form
parentform.close(.f.)

'Opens sites and runs saved query on Equate
query.filter = "trim(Sites->Equake)=\"Y\""
query.order = ""


'Open the layout_type showing just the records that satisfy the filter
DIM Shared varP_Sites as P
DIM layout_name as c 
layout_name = "Sites"


dim tempP as p
'Get pointer to existing window. In case layout_name is qualified with a dictionary name, extract up to first @. In case formname has spaces, normalize it
tempP=obj(":"+object_name_normalize(word(layout_name,1,"@")))
'Test if pointer is valid
if is_object(tempP) then 
'Test if pointer refers to a form or browse
if tempP.class() = "form" .or. tempP.class() = "browse" then 
'Apply the query to the form or browse as the Base query. (this means that 
'the user cannot turn the query off, only add to the query)
tempP.BaseQueryRun(query.filter,query.order)
'then activate the already open window
tempP.activate()
else
'Window is not already open, so open it
varP_Sites = :Form.viewqueried(layout_name,query.filter, query.order )

end if
else 
varP_Sites_Plus = :Form.viewqueried(layout_name,query.filter, query.order )

end if
xbasic_wait_for_idle()
tbl.close()
end if

[Cheryl Lemire]

Wanda,

Stan is correct. You apparently combined my code with Mike's so you have a lot of unneccessary lines. I would follow his suggestion, yes there is no harm by leaving it, but if you are beginning your lessons in coding, no reason to include code that is not needed :)

[Stan Mathews]

Wanda,

Stan is correct. You apparently combined my code with Mike's so you have a lot of unneccessary lines. I would follow his suggestion, yes there is no harm by leaving it, but if you are beginning your lessons in coding, no reason to include code that is not needed :)

Plus if the unnecessary code is left in and you try to use it later in constructing another script, you could well get confused. The portion

'Are there matching records present in the table?
dim global nrecs as N
nrecs= a5_get_records_in_query("sites","equake=\"Y\"")
IF (nrecs = 0) then
ui_msg_box("Null Query","There are no matching records in this search, unable to proceed" ,UI_INFORMATION_SYMBOL)
end 'If there are no matching records, script ends here
else
'other code here as in your current script
end if

can be used anywhere you want to test for records fitting a query, such as before a report is run, etc. All you have to do is alter the

nrecs= a5_get_records_in_query("sites","equake=\"Y\"")

by substituting a different table name and a different filter.

[Wanda Tucker]

Okay, Stan, this is what drives me nuts! I spent 20 minutes or so trying to decipher the code in your sample - key word is "trying". Apparently, code is pretty self explanatory to most people - but not at all to me. Maybe I can get a bit of it - sort of like the blind "seeing only the tail of an elephant and thinking it's a snake".

Just when you have time or decide to delve further. Pretty self explanatory in usage. Code behind buttons is heavily commented.

Here is the code on a button from the example you sent:

'Date Created: 24-May-2006 09:07:58 AM
'Last Updated: 24-May-2006 09:47:50 AM
'Created By : Stan Mathews
'Updated By : Stan Mathews
tbl = table.open("data_table",FILE_RW_SHARED) ' open table with pointer variable tbl
IF var->alogical = .t. ' set up filter to choose records
query.filter = "deceased" ' special handling of logical comparison
ELSE
query.filter = ".not. deceased"
END IF
query.order = "deceased" ' set up order to display records if any found
query.options = "I" ' not strictly required but suggested by documentation
query.description = "Temp Deceased" ' just for info
ix = tbl.query_create() ' create query with pointer ix
recs = ix.records_get() ' use .records_get() method to get record count
if recs = 0 ' if we didn't find any records
ui_msg_box("Sorry","No entries found for deceased "+ var->alogical ) ' do the code inside the if ... end if
ix.drop() ' get rid of useless query
tbl.close() ' close table
end ' then stop

end if
tbl.close() ' close table

'any other code you wanted to run if there were records would go down here like .....
'same for all four buttons

DIM Shared varP_Saved_Browse as P
DIM layout_name as c
layout_name = "Saved Browse" 'just the name I saved the browse as
DIM tempP as p
'Get pointer to existing window. In case layout_name is qualified with a dictionary name, extract up to first @. In case formname has spaces, normalize it
tempP=obj(":"+object_Name_normalize(word(layout_name,1,"@")))
'Test if pointer is valid
if is_object(tempP) then
'Test if pointer refers to a form or browse
if tempP.class() = "form" .or. tempP.class() = "browse" then
'If so, then activate the already open window
tempP.activate()

else
'Window is not already open, so open it
varP_Saved_Browse = :Browse.view(layout_name)


end if
else
varP_Saved_Browse = :Browse.view(layout_name)


end if

ix.drop() ' get rid of query after it has been used

My wonderment is in several areas, such as line 5...what is FILE_RW_SHARED?

Line 7 indicates that the query is named "deceased", yet line 12 indicates that the description of the query is "Temp Deceased". My wonderment is, which is it - deceased or temp deceased? Or, maybe there are two queries in this code?

Line 13 - What's an ix pointer and why is it needed? If I use the ix pointer in the code I'm really trying to get ironed out, will that handle nesting queries?

Line 23 - what is meant by, "In case layout_name is qualified with a dictionary name..." Huh?

Line 24 - What does the @ symbol do, and what does the ,1, mean prior to the ending@?

Towards the end, reference is made the VarP_Saved_Browse...if the browse is saved, then why is a variable needed? My only use of variables is when the variable returns some sort of temporary data.

See? It's more greek than not to me. See why I hate code? What's a person to do, eh, when they simply don't get it, in spite of hours and hours and hours over the years trying to figure the language out.

The coding needed for the first computer I ever worked on - a TRS80 (remember the Trash 80?) made more sense than XBasic to me. I'm not dogging Alpha, because I know that 99.9999999% of Alpha developers actually "get" code language. But I don't.

I'm ready to give up and accept it, just about.

W

[Wanda Tucker]

Plus if the unnecessary code is left in and you try to use it later in constructing another script, you could well get confused. The portion

To my knowledge I didn't combine them - but who knows? And I don't dare start chopping away at it - it'd be the next century before I can get it to work again...even with all this instruction I'm getting.

All I need to know now is how to nest the queries...but I'm not going to sweat it if I don't. The user will just have to learn how to use the filter button within the Sites form. I figure it's much easier to teach a user what the filter button does than to waste county dollars on trying to understand a piece of code.

In fact, I'm very sorry to waste your and Stan and Mike's time on this, as well...just a bit more and I'll be done (nesting the queries).

Many thanks,
Wanda

[Stan Mathews]

My wonderment is in several areas, such as line 5...what is FILE_RW_SHARED?

a mode of opening the table, options are available for FILE_ReadWrite_SHARED, FILE_Read_Only_SHARED, etc. The option chosen is probably best for a multi user environment unless you know you need EXCLUSIVE access.

Line 7 indicates that the query is named "deceased", yet line 12 indicates that the description of the query is "Temp Deceased". My wonderment is, which is it - deceased or temp deceased? Or, maybe there are two queries in this code?

Line 7 indicates that the filter for the query is "deceased", the description is a different thing.

Line 13 - What's an ix pointer and why is it needed? If I use the ix pointer in the code I'm really trying to get ironed out, will that handle nesting queries?

- When you establish a pointer variable with ix = tbl.query_create() you can then use the methods available for the pointer like .records_get(). As an analogy, the ix pointer variable is like a food processor. You can plug in whatever tools (methods) that you have that work with the food processor, shredder, slicer, dicer, crusher, whatever.

Line 23 - what is meant by, "In case layout_name is qualified with a dictionary name..." Huh?

the code that opens the browse is a direct copy of the xbasic revealed when you create an action script to open a browse, reusing an existing instance if there is one (not previously closed and maybe not visible) If you know the browse you want to open is the only one with a certain name and you know it has been previously closed, all you really need is

:Browse.view(layout_name)

where layout_name is the browse you want to open, quoted, inside the parentheses.

Line 24 - What does the @ symbol do, and what does the ,1, mean prior to the ending@?

when examining anything unfamiliar, start with the inner portions first instead of trying to understand it in the context of the whole line. In this use the Output_String as C = WORD( Input_String as C, Word_Number as N [, Word_Delimiter as C [, Word_Count as N ]] ) function is used to return the first word in layout_name where the divider is "@"

word(layout_name,1,"@"))

You could have browses named "test" for tables named "sites" and "people". The fully qualified names of these two browses would be "[email protected]" and "[email protected]"

The word function returns the portion "test".

Towards the end, reference is made the VarP_Saved_Browse...if the browse is saved, then why is a variable needed? My only use of variables is when the variable returns some sort of temporary data.

same comment, if you know you have unquely named browses and that they are not already opened, then just use the line :Browse.view(layout_name) with your browse name.

[Stan Mathews]

To my knowledge I didn't combine them - but who knows? And I don't dare start chopping away at it - it'd be the next century before I can get it to work again...even with all this instruction I'm getting.

All I need to know now is how to nest the queries...but I'm not going to sweat it if I don't. The user will just have to learn how to use the filter button within the Sites form. I figure it's much easier to teach a user what the filter button does than to waste county dollars on trying to understand a piece of code.

In fact, I'm very sorry to waste your and Stan and Mike's time on this, as well...just a bit more and I'll be done (nesting the queries).

Many thanks,
Wanda

I thought you found your answer about nesting the queries in the other thread when you noted something about having to have the query button(s) on a form not based on the table/set being queried.

Most developers use menu forms based on tables created specifically for the purpose of not opening data tables just to let a user push a button. Take a look at Menu forms and look at the table behind the main menu in AlphaSports.

[Wanda Tucker]

Dang, you guys just won't give up on me! I'm humbled. Will mull over your explanations and maybe I'll see a little flicker of light. :)
W

[Wanda Tucker]

I thought you found your answer about nesting the queries in the other thread when you noted something about having to have the query button(s) on a form not based on the table/set being queried.

I did. But the next day it didn't behave the same, so I'm back at the beginning of that idea/need.
W

[Stan Mathews]

Dang, you guys just won't give up on me! I'm humbled. Will mull over your explanations and maybe I'll see a little flicker of light. :)
W

For example you could have this code for a button, anywhere in your application.

'Are there matching records present in the table?
dim global nrecs as N
nrecs= a5_get_records_in_query("sites","equake=\"Y\"")
IF (nrecs = 0) then
ui_msg_box("Null Query","There are no matching records in this search, unable to proceed" ,UI_INFORMATION_SYMBOL)
end 'If there are no matching records, script ends here
'no point in opening an empty browse
else
'otherwise we do have records to show so ......
layout_name = "the actual name of browse you want to open"
:Browse.viewqueried(layout_name,"equake=\"Y\"") 
end if

[Cheryl Lemire]

I would like to take this time to thank Wanda, Mike, and Stan for this thread. As a result I was able to modify my function to just a few lines. I don't use an 'else' in my function though, I simply end it if nrecs=0. Since I call my function in an 'event' somewhere on a form, if I need 'something' else to happen, I code that portion in the event itself after calling my function. Here is my revised function:

FUNCTION matching_records AS C (table_name AS C, filter_name AS C)
    
'-------------------------------------------------------------------------------
' matching_records() function created by CKL 05/14/2006
'-------------------------------------------------------------------------------

'*******************************************************************************
' PRIMARY PURPOSE of the matching_records() function is to verify that there
' are matchibg records in a table based on the parameters.
'
' Parameters:
'
' matching_records("table_name", "filter_name")
'    table_name    -    sets the table/set to query
'    filter_name    -    sets the filter

' ADDITIONAL FEATURES
' - If no matching records are found, the user receives a message box and the
'    script ends.

' REVISIONS
' 20060524 CKL
'    - Modify to use alpha built in function a5_get_records_in_query()
'    - Remove order_name parameter, no longer needed with built in function
'*******************************************************************************

'Are there matching records present in the table?
dim global nrecs as N
nrecs= a5_get_records_in_query(table_name,filter_name)    'returns the number of records in the specified table or set that satisfy a query expression.
IF (nrecs = 0) then
ui_msg_box("Null Query","There are no matching records in this search, unable to proceed" ,UI_INFORMATION_SYMBOL)
end 'If there are no matching records, script ends here
end if
xbasic_wait_for_idle()
    
END FUNCTION

An example of how I use the above: I have a script that displays a dialog showing a po number and a ship date, when the user clicks the ok button - I check to see if the po number exists, if it does not ... the script ends, if it does exist, my script continues as follows:

'=======================================================================

'Are there matching records present in the table?
matching_records("nceinvn", "nceinvn->nce_p_o_ = Var->vcgNCEPO")    '20060524 CKL removed order_name parameter

IF (nrecs = 0) then
    parentform:b_update.activate()
    end     'If there are no matching records, script ends here
end if

xbasic_wait_for_idle()
 
'get here only if the search returned matching records in the table

'=======================================================================

Wanda, you made a comment earlier in the thread:

How do you whizzes create code this quickly?!

I can't speak for other developers, but I am not a whiz, nor do I create code quickly. If you see me posting code samples, it is because I have used them in the past.

I have spent hours trying to get code to work and do what I want in the end. The fact that I take the time to read the help docs and ask for help here on the forum is what has allowed me to learn what I have so far. If I did not spend hours trying all possible scenarios in my code prior to asking for help, I probably would not understand it as well.

There is still code that I use that I do not fully understand, but I understand enough of it to know what can be changed to get the desired results. And when I don't, I come here :)

[Wanda Tucker]

For example you could have this code for a button, anywhere in your application.

'Are there matching records present in the table?
dim global nrecs as N
nrecs= a5_get_records_in_query("sites","equake=\"Y\"")
IF (nrecs = 0) then
ui_msg_box("Null Query","There are no matching records in this search, unable to proceed" ,UI_INFORMATION_SYMBOL)
end 'If there are no matching records, script ends here
'no point in opening an empty browse
else
'otherwise we do have records to show so ......
layout_name = "the actual name of browse you want to open"
:Browse.view(layout_name) 
end if

Now, that makes sense! Maybe code is sort of like algebra to some people...struggle, struggle, don't get it for weeks/months, then all of a sudden something clicks (no pun intended). :)

So, I take it that this code is simply for running a saved query, then opening the browse to show the records in the query, or, not opening the browse when no records are found by the query. Right?

[Stan Mathews]

Now, that makes sense! Maybe code is sort of like algebra to some people...struggle, struggle, don't get it for weeks/months, then all of a sudden something clicks (no pun intended). :)

So, I take it that this code is simply for running a saved query, then opening the browse to show the records in the query, or, not opening the browse when no records are found by the query. Right?

Almost. The line

nrecs= a5_get_records_in_query("sites","equake=\"Y\"")

queries the sites table filtering for equake = "Y"

No saved query involved. It displays a specified browse showing the results of the query only if there are records that satisfy equake = "Y".

Now consider a form where you have created a variable, say yesorno and displayed it on the form. The user can enter "Y" or "N" or any other letter.

You change the nrecs= a5_get_records_in_query("sites","equake=\"Y\"")

to

nrecs= a5_get_records_in_query("sites","equake="+quote(var->yesorno))

If the user enters Y in the variable on the form, they get shown the browse containing records where equake="Y". It the user enters N, they get shown the browse containing records where equake="N". If they enter any other letter, assuming there are only Y and N in the table field equake, they get the message in the ui_msg_box().

[Wanda Tucker]

[QUOTE=
I can't speak for other developers, but I am not a whiz, nor do I create code quickly. If you see me posting code samples, it is because I have used them in the past.

I have spent hours trying to get code to work and do what I want in the end. The fact that I take the time to read the help docs and ask for help here on the forum is what has allowed me to learn what I have so far. If I did not spend hours trying all possible scenarios in my code prior to asking for help, I probably would not understand it as well.

There is still code that I use that I do not fully understand, but I understand enough of it to know what can be changed to get the desired results. And when I don't, I come here :)[/QUOTE]

Most of my hours are spent learning and using the incredible Action Scripting. The Help files, I find confusing most of the time, to be honest. With code, I'd enjoy spending time, but don't have the time to spend, unfortunately - like adding my hours up this week just to get one button to work (which still doesn't nest queries) by way of code, comes to about 10 - 12 hours. I'd get nothing else done, and still need to spend hundreds of hours on any other code I might need. So, there you have it. It's like doing laundry in a river that takes all day - or using an automatic washer that takes about 45 minutes. If you can't afford all day, time-wise, then the washer is a wonderful tool. The trade-off is that you know how the clothes get clean at the river - but have no clue how a washer works, yet it works better and faster.

Given tons of unexpecteds to deal with at my new retail store (like the database developer quitting on me in mid-stream, and dealing with inventory suppliers who don't ship what you order, yet charge you for returning the goods...blah, blah, blah...) my stress level has been exceptionally high, lowering my tolerance level.

I'm done for the day. Thank you!\
Wanda