WhereBuilder Object

The WhereBuilder Object is a helper object to build where expressions from a script. Where expressions are used to filter a request by applying extra conditions. These expressions are generally stored as an XML-formatted string, however, the scripting implementation can unwrap these in a tree. The WhereBuilder object can be used to create new instances of these objects. WhereBuilder can be accessed from any script, because it is a globally accessible type, just use it like: WhereBuilder.createNull() to create a new null where object.

The code snippet below shows how the WhereBuilder Object can be used:

var Fields = ['Id','Name','Phone','Address','Remarks','Discount'];
var Expression = WhereBuilder.createBinary( WhereBuilder.createField('Id'), WhereBuilder.createConstant('CustomValue'), 'Equal');
var result = lda.selectWhere('Customers',Fields,Expression,{});

Functions

createBinary(left, right, operator)

Creates a WhereBinary Object; use this to create a where binary expression, like field = 15.

createUnary(value, operator)

Creates a WhereUnary Object, unary expressions are negations or binary NOT operations.

createList(args...)

Creates a WhereList Object, lists are used with the IN operator to determine if a value is in a list of others.

createParameter(name, type, size)

Creates a WhereParameter Object. Parameters are stored externally and can be used to pass blobs as where expressions.

createConstant(value, type)

Creates a WhereConstant Object. Constants can be any literal value.

createNull()

Creates a WhereNull Object. This represents the SQL null construct.

createField(table, field)

Creates a WhereField Object. This is a reference to a field in the table in the table parameter.

createMacro(name, args...)

Creates a WhereMacro Object. See the Macro Processor for more information on macros and when to use them.

createBetween(value, lower, upper)

Creates a WhereBetween Object. The value parameter will be compared to lower and upper, it has to be greater or equal to lower, and less than or equal to upper.

createFunctionCall(value, kind)

Creates a function-call expression (see FunctionCallExpression) that represents a server-side SQL function call (such as Trim or Length) applied to value.

createDateTimeNow()

Creates an expression that represents the current database server date and time (see DateTimeNowExpression).

createDateTimeToday()

Creates an expression that represents the current database server date (see DateTimeTodayExpression).

createDateTimePart(value, part)

Creates an expression that extracts a part (such as year or month) of the given date value (see DateTimePartExpression).