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Find Mode is a special mode that can be assumed by a foundset object to perform data searches using a powerful, high-level abstraction. When in Find Mode, the foundset's Data Providers, normally used to read/write data, are instead used to enter search criteria. Any data provider can be assigned a search condition which should evaluate to a String, Number or Date. Because forms typically bind to a foundset, criteria may be entered from the GUI by the user or programmatically.

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Code Block
 SELECT customerid FROM customers WHERE (city = ?  AND postalcode = ?) OR (city = ?  AND postalcode = ?) ORDER BY customerid ASC //Query params: ['Berlin','12209','San Fransisco','94117']

Finding

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Records Through a

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Relation

Find Mode is very flexible as searches can traverse the entire data model. When a foundset enters find mode, any foundset related to a search record can be used to enter criteria. Moreover, related foundsets can use multiple search records so any permutation of Logical AND / OR is possible.

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Code Block
// Find customers with one or more orders containing one or more products supplied by a vendor in USA
if(foundset.find()){
    customers_to_orders.orders_to_order_details.order_details_to_products.products_to_suppliers.country = 'USA';
    foundset.search();
}

Finding

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Records within a

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Related Foundset

It is worth pointing out that related foundsets may be put into Find Mode as well. The foundset will maintain the constraints imposed by the relation in addition to the criteria specified in the data providers.

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Servoy's Find Mode provides several special operators that when used in combination can articulate the most sophisticated search requirements.  Operators and operands should be concatenated as strings.

Operator

Description

Applicable Data Types

Example

||

OR: Used to implement a logical OR for two or more search conditions in the same data provider

Any

Code Block
 // Cities of London or Berlin
city = 'Berlin||London';

|

Format: Used to separate a value and an implied format.

Date

Code Block
 // exactly 01/01/2001 (00:00:00 implied)
orderdate = '01/01/2001|MM/dd/yyyy';

!

Not: Used to implement a logical NOT for a search condition.

Any

Code Block
// Anything but Berlin
city = '!Berlin';

#

Sensitivity Modifier: Implies a case-insensitive search for text columns. Implies a match on entire day for date columns.

Text, Date

Code Block
// i.e. Los Angeles, lOS aNGeLES
city = '#los angeles';

// any time on 01/01/2001
orderdate = '#01/01/2001|MM/dd/yyyy';

^

Is Null: Matches records where a column is null.

Any

Code Block
// All null contact names, not including empty strings
contactname = '^';

^=

Is Null/Empty/Zero: Matches records where a column is null, empty string value or zero numeric value

Text, Numeric

Code Block
// All freights which are null or 0
freight = '^=';

<

Less than: Matches records where the column is less than the operand

Any

Code Block
// i.e. 50, 99.99, but not 100, 101
freight = '<100';

<=

Less than or equal to: Matches records where the column is less than or equals the operand

Any

Code Block
// i.e. Atlanta, Baghdad, Berlin, but not Buenos Aires, Cairo
city = '<=Berlin';

>=

Greater than or equal to: Matches records where the column is greater than or equals the operand

Any

Code Block
// Any time on/after 12am new year's day 2001
orderdate = '>=01/01/2001|MM/dd/yyyy';

>

Greater than: Matches records where the column is greater than the operand

Any

Code Block
// i.e. 100.01, 200, but not 99,100
freight = '>100';

...

Between: Matches records where the column is between (inclusive) the left and right operands.

Any

Code Block
// Any time during the year 2001
orderdate = '01/01/2001...01/01/2002|MM/dd/yyyy';

// i.e.
freight = '100...200';

// i.e. London, Lyon, Madrid, Omaha, Portland
city = 'London...Portland';

%

Wild Card String: Matches records based on matching characters and wild cards

Text

Code Block
city = 'New%';    // Starts with: i.e. New York, New Orleans
city = '%Villa%; // Contains: i.e. Villa Nova, La Villa Linda
city = '%s';     // Ends with: i.e. Athens, Los Angeles

_

Wild Card Character: Matches records based on

Text

Code Block
// i.e. Toledo, Torino
city = '%To___o%';

\

Escape Character: Used to escape other string operators

Text

Code Block
// Escape the wild card, i.e. ...50% of Capacity...
notes = '%\%%';

now

Now: Matches records where the condition is right now, including time

Date

Code Block
// exact match on this second
creationdate = 'now';

today

Today: Matches records where the condition is any time today

Date

Code Block
// match on anytime today
orderdate = 'today';

Using find mode from scripting without using special operators or spaces

You can use find mode with non-strings as well. For example, dates, numbers are not interpreted and will be used literally.

Arrays can be used when searching for multiple values, these are also not interpreted.

Code Block
if(foundset.find()) {
    city = ['Berlin', 'Amsterdam'] // city in (?, ?) {'Berlin', 'Amsterdam'}
    companyid = 42; // literal numerical value
    startdate = new Date(99,5,24,11,33,30,0); // literal date value
    foundset.search();   // Execute the query and load the records
}

Note that when you use a string for searching, it will be trimmed (except in case of a CHAR column, which is padded with spaces by the database).

If you want to make sure the argument is not interpreted, us a single-element array:

Code Block
if (foundset.find()) {
    // tag = ' Hello Servoy ';     // would search for trimmed    
    tag = [' Hello Servoy '];     // will search for literal (untrimmed)
    foundset.search();   // select ... from ... where tag = ? {' Hello Servoy '}
}

Find Mode and the User Interface

The above examples deal with find mode in which find mode is entered, criteria are expressed and the search is run, all in a single action. The effect of the search is entirely up to the developer. However, find mode can also be entered in one action and searched in another action. In between, the user may manually enter values into fields to express the search criteria. They can then run the search action and a form's foundset will show the results of the search. Any of the above search criteria may be used.

Example In this example there is a method which can both enter find mode as well as run a search when in find mode. In between the two different invocations of this method, the user interface is ready to receive input from the user. When complete, the user may run the method again, this time the foundset will search for results.

Code Block
/**
 * @AllowToRunInFind
 *
 * @properties={typeid:24,uuid:"088B830C-2A4F-483C-A135-5FA32A010AE9"}
 */
function doFind(){
	if(foundset.isInFind()){    // if the foundset is already in find mode, run the search
		foundset.search();
	} else {
		foundset.find();    // otherwise, enter find mode
	}
}
Note

Find mode blocks the execution of any methods which are normally invoked from the user interface. This is a good thing as these methods may have unintended consequences when a form's foundset is in find mode. Notice the JSDocs tag @AllowToRunInFind in the comment block which precedes the method. This tag provides the metadata to let Servoy know that this method should be allowed to run while the form's foundset is in find mode. Without this exception, this method would be blocked from execution, and there would be no recourse to programmatically exit find mode.

Read-Only Fields

By default, even read-only fields will become editable for the duration of the find mode. This is often useful, because while a data provider may not be available to edit, in find mode, it becomes a vehicle to enter a search criterion and should be editable to the user. However, in some cases it may be desired that read-only fields remain so for the duration of find mode as well. Servoy provides a UI property which may be set through the Application API using the method setUIProperty.

Example This example is identical to the above example with the exception, that for the duration of this find, the read-only property of fields is maintained. After a find, it is set back to the default so as not to interfere with other functionality throughout the rest of the application.

Code Block
/**
 * @AllowToRunInFind
 *
 * @properties={typeid:24,uuid:"088B830C-2A4F-483C-A135-5FA32A010AE9"}
 */
function doFind(){
	if(foundset.isInFind()){
		foundset.search();
		application.setUIProperty(APP_UI_PROPERTY.LEAVE_FIELDS_READONLY_IN_FIND_MODE, false)    // reset to the default
	} else {
		application.setUIProperty(APP_UI_PROPERTY.LEAVE_FIELDS_READONLY_IN_FIND_MODE, true);    // before entering find mode, enforce read-only fields
		foundset.find();
	}
}

Canceling Find Mode

Find mode can be programmatically cancelled by invoking the loadAllRecords method of the foundset. The foundset will revert to the query prior to entering find mode. Within the Smart Client the user can cancel Find mode by pressing Escape. This will trigger the loadAllRecords command of the Form to which the foundset is bound.

Complex Searches

Servoy's find mode can be used to easily satisfy even complex search requirements. Remember that any related foundset may be used to enter criteria and that any number of search records may be used in any foundset and any operators may be used in combination for every data provider.