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SAP OS QUERY COMPS documentation, setup help and example usage
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Query Service Components
A query is represented by a query object, which is managed by a Query Manager (also an object). The Query Manager represents the query service with respect to the ABAP program.
To create a Query Manager, you need the static method
GET_QUERY_MANAGER of the general system service class CL_OS_SYSTEM .
An ABAP program does not work with the Query Manager and queries by using class reference variables. Instead, it uses the interfaces IF_OS_QUERY_MANAGER , IF_OS_QUERY , and IF_OS_QUERY_FACTORY .
A query is not executed directly, but using the method
GET_PERSISTENT_BY_QUERY of the interface
IF_OS_CA_PERSISTENCY of a class agent. This means a search is carried out for persistent objects of the associated persistent class that match the filter condition.
The options for executing a query are controlled using the interface IF_OS_QUERY_OPTIONS . To enable this, a structure of type IF_OS_QUERY_OPTIONS= OPTIONS can be passed to method GET_PERSISTENT_BY_QUERY .
Relevant Method of the System Service
Most of the components of the system service class CL_OS_SYSTEM are used internally by the Object Services. A method must be used in an application program to be able to work explicitly with object-oriented queries.
This static method returns the return value RESULT of type
IF_OS_QUERY_MANAGER containing a reference to the Query Manager. The Query Manager is created when you initialize the Object Services.
Methods of the Query Manager
The Query Manager manages the object-oriented queries of the ABAP program and is executed from interface
IF_OS_QUERY_MANAGER .
Creates a query and returns a reference to the query object in return value RESULT of type IF_OS_QUERY . The filter condition is passed to the parameter I_FILTER of type string . The sort condition is passed to the parameter I_ORDERING of type
string . If the query�s parameters are specified using a parameter list, this must be passed to the parameter I_PARAMETERS of type string .
Methods of a Query
Queries are executed from interfaces
IF_OS_QUERY and
IF_OS_QUERY_EXPR_FACTORY .
Methods of the Interface IF_OS_QUERY
Returns a reference to a query expression factory in the return parameter RESULT of type IF_OS_QUERY_EXPR_FACTORY . Technically speaking, a query expression factory is part of a query object, although it is executed using the interface
IF_OS_QUERY_EXPR_FACTORY , like a separate object.
Sets the filter condition. The internal display of the filter condition that is created with a query expression factory is passed to parameter I_FILTER_EXPR of type IF_OS_QUERY_FILTER_EXPR .
Sets the parameter list of the filter condition. The internal display of the parameter list that is created with a query expression factory is passed to parameter I_PARAMETERS_EXPR of type
IF_OS_QUERY_PARAMETERS_EXPR .
Sets the sort condition. The internal display of a sort condition created with the query expression factory is passed to parameter
I_ORDERING_EXPR of type IF_OS_QUERY_ORDERING_EXPR .
Creates the internal displays of the filter condition, the parameter list, and the sort term if these have not yet been created or set.
Methods of the Interface IF_OS_QUERY_EXPR_FACTORY
Creates either a filter condition in the form
attr1 operator attr2 ,
where attr1 , operator , and attr2 are the values of parameters I_ATTR , I_OPERATOR and I_ATTR2 .
attr1 operator 'val' or
attr1 operator val_w_quotes
where val and val_w_quotes are the values of parameters I_VAL and I_VAL_W_QUOTES .
If parameter I_IDX of type i is passed, val is the value of the parameter from the parameter list, for which the index when the query is executed is determined by the value of parameter
.
The filter condition that is created is returned in the return value RESULT of type IF_OS_QUERY_FILTER_EXPR .
Creates a filter condition in the following form (depends on the value of I_NOT parameter)
attr [NOT] LIKE 'pattern' or
attr [NOT] LIKE pattern_w_quotes ,
where attr , pattern , and pattern_w_quotes are the values of the parameters I_ATTR , I_PATTERN and
I_PATTERN_W_QUOTES .
If parameter I_IDX of type i is passed, pattern
is the value of the parameter from the parameter list, for which the index when the query is executed is determined by the value of parameter
I_IDX .
Specifying parameter I_ESCAPE or I_ESCAPE_W_QUOTES appends the definition of an escape character in form
escape_w_quotes are the values of parameters I_ESCAPE and
I_ESCAPE_W_QUOTES .
The filter condition that is created is returned in the return value RESULT of type IF_OS_QUERY_FILTER_EXPR .
Creates a filter condition in the following form (depends on the value of I_NOT parameter)
attr IS [NOT] NULL ,
where attr is the value of parameter I_ATTR .
The filter condition that is created is returned in the return value RESULT of type IF_OS_QUERY_FILTER_EXPR .
Creates a filter condition in the form
attr EQUALSREF ref ,
where attr is the value of parameter I_ATTR and ref
is the value of the parameter from the parameter list whose index when the query is executed is determined by the value of parameter
.
Instead of using a parameter to set the persistent object reference, you can specify the instance GUID and class GUID using parameters I_GUID and I_CLSGUID of type OS_GUID .
The filter condition that is created is returned in the return value RESULT of type IF_OS_QUERY_FILTER_EXPR .
Creates a filter condition in the form
NOT ( expr ),
where expr is a filter condition that has already been created and passed to parameter I_EXPR .
The filter condition that is created is returned in return value
RESULT .
Creates a filter condition in the form
( expr1 ) AND ( expr2 )
where expr1 or expr2 are filter conditions that have already been created and passed to parameter I_EXPR1 or
I_EXPR2 .
The filter condition that is created is returned in return value
RESULT .
Creates a filter condition in the form
( expr1 ) OR ( expr2 )
where expr1 or expr2 are filter conditions that have already been created and passed to parameter I_EXPR1 or
I_EXPR2 .
The filter condition that is created is returned in return value
RESULT .
Creates a parameter list. The paremeter list that is created is returned in return value RESULT of type IF_OS_QUERY_PARAMETERS_EXPR
.
The parameters are appended in succession when method APPEND of a further interface
IF_OS_QUERY_PARAMETERS_EXPR is called. The parameter name is passed to parameter I_PAR .
Creates a sort condition. The sort condition is returned in the return value RESULT of type IF_OS_QUERY_ORDERING_EXPR .
The attributes that you are sorting by are appended one after the other when you call method APPEND_ASCENDING or APPEND_DESCENDING
of additional interface
IF_OS_QUERY_ORDERING_EXPR . The parameter name is passed to parameter I_ATTR .
Documentation extract taken from SAP system, � Copyright SAP AG. All rights reserved
