Dynamic Where XML Format

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Query node

The root node of the DynamicWhere expression is the query node. It has two mandatory attributes: xmlns and version.

• The xmlns attribute has this value: http://www.remobjects.com/schemas/dataabstract/queries/5.0
• The version attribute specifies the format version of the DynamicWhere expression; the current version is 5.0

Sample

<query 
  xmlns="http://www.remobjects.com/schemas/dataabstract/queries/5.0" 
  version="5.0">
</query>

Where node

Each query node should have only one where node. The where node has no attributes. It can hold only one of the following nodes:

• binaryoperation - represents BinaryExpression;
• unaryoperation - represents UnaryExpression;
• constant - represents ConstantExpression;
• list - represents ListExpression;
• parameter - represents ParameterExpression;
• field - represents FieldExpression;
• null - represents NullExpression;
• macro - represents MacroExpression;

Sample

<query 
  xmlns="http://www.remobjects.com/schemas/dataabstract/queries/5.0" 
  version="5.0">
    <where>
      ...
    </where>
</query>

Binaryoperation node

The binaryoperation node represents a BinaryExpression instance. It must have exactly two nodes, representing the Left and the Right expressions that the operator applies to. The operator attribute can have the following values:

And Or Xor

Less LessOrEqual Greater

GreaterOrEqual NotEqual Equal

Like In Addition

Subtraction Multiply

Sample

<binaryoperation operator="Equal">
  <field>EmployeeID</field>
  <constant type="Integer" null="0">5</constant>
</binaryoperation>

UnaryOperation node

The unaryoperation node represents the UnaryExpression instance. It can have only one node and operator attribute.

Sample

<unaryoperation operator="Not">
  <null />
</unaryoperation>

or just

<unaryoperation>
  <null />
</unaryoperation>

Constant node

The constant node represents the ConstantExpression instance. Inside Dynamic Where it is usually used as right expression inside the binaryoperation node.

It has a type attribute that specifies the type of constant. The type can be any of following:

AutoInc Blob Boolean Byte Cardinal

Currency DateTime Decimal Float Guid

Integer LargeAutoInc LargeInt LargeUInt Memo

ShortInt SingleFloat SmallInt String Unknown

WideMemo WideString Word Xml

The null attribute shows the value null or not. It can take values 0 (which means the value is NOT null) or 1 (meaning the value IS null)

Sample

<constant type="Integer" null="0">5</constant>

or

<constant type="String" null="0">King</constant>

Parameter node

The parameter node represents ParameterExpression. The value of the parameter node is the parameter name. This node has the following attributes:

• type attribute that specifies the type of the parameter. Type can be any of following:

AutoInc Blob Boolean Byte Cardinal

Currency DateTime Decimal Float Guid

Integer LargeAutoInc LargeInt LargeUInt Memo

ShortInt SingleFloat SmallInt String Unknown

WideMemo WideString Word Xml

• The size attribute is optional and is usually used with String, WideString, Memo, WideMemo, Blob types. 0 � is the default value.

Sample

<parameter 
  type="String" 
  size="50">pEmployeeName</parameter>

or

<parameter 
  type="Integer" 
  size="0">pEmployeeID</parameter>

Field node

The field node represents the FieldExpression, which is the field reference of the table in the schema.

Sample

<field>EmployeeID</field>

or

<field>FirstName</field>

Null node

The null node represents the NullExpression. It is usually used as part of unary expressions.

Sample

<unaryoperation operator="Not">
  <null />
</unaryoperation>

Macro node

The macro node represents the MacroExpression. It has a name attribute as the macros name. If the macros takes parameters, they should be listed as expression nodes inside the macro node, as you can see in the sample below:

Sample

<macro name="UpperCase">
  <constant type="String" null="0">test</constant>
</macro>

DataTypes formats

Type	Sample Value	Description
AutoInc	15	integer value as string.
Blob	BF12F25POD4556KF	value encoded to Base64 string format.
Boolean	True	True or False.
Byte	2	value as string.
Cardinal	1234	in string format.
Currency	123,45->1234500	with accuracy 4 number after comma as integer in string format.
DateTime	1231505053	Unix/Linux style date-and-time value as int64 in string format.
Decimal	125	as decimal in string format.
Float	12.34	as double in string format.
Guid	6C8DE133-9E4D-433A -BC4E-D4A1E49EAAB0	as string in following format xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx without braces.
Integer	52	value as string.
LargeAutoInc	4585	value as string.
LargeInt	5414	value as string.
LargeUInt	41	value as string.
Memo	"This is the long text"	value as string.
ShortInt	15	value as string.
SingleFloat	32.14	as double in string format.
String	"Just text value"	value as string.
Unknown	-	not supported in Dynamic Where.
WideMemo	"This is the long text"	value as string.
WideString	Just text value	value as string.
Word	2	value as string.
Xml	<node attr="1"> AAA</node>	outer xml as string.

Some complex samples of the Dynamic Where expressions

<query xmlns="http://www.remobjects.com/schemas/dataabstract/queries/5.0" version="5.0">
  <where>
    <binaryoperation operator="And">
      <binaryoperation operator="Equal">
        <field>EmployeeID</field>
        <parameter type="Integer" size="0">pEmployeeID</parameter>
      </binaryoperation>
      <binaryoperation operator="Equal">
        <field>FirstName</field>
        <parameter type="String" size="50">pEmployeeName</parameter>
      </binaryoperation>
    </binaryoperation>
  </where>
</query>

<query xmlns="http://www.remobjects.com/schemas/dataabstract/queries/5.0" version="5.0">
  <where>
    <binaryoperation operator="Or">
      <binaryoperation operator="And">
        <binaryoperation operator="Equal">
          <field>EmployeeID</field>
          <parameter type="Integer" size="0">pEmployeeID</parameter>
        </binaryoperation>
        <binaryoperation operator="Equal">
          <field>FirstName</field>
          <parameter type="String" size="50">pEmployeeName</parameter>
        </binaryoperation>
      </binaryoperation>
      <binaryoperation operator="In">
        <field>LastName</field>
        <list>
          <constant type="String" null="0">Fuller</constant>
          <constant type="String" null="0">King</constant>
          <constant type="String" null="0">Test</constant>
        </list>
      </binaryoperation>
    </binaryoperation>
  </where>
</query>

Product: RemObjects Data Abstract
Available Editions: Data Abstract for .NET, Delphi and Xcode

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