SYNTAX:
xpxSelectAggrInstancesEx (aggrId : AGGREGATE OF GENERIC; modelVersion : INTEGER; condition : STRING; options : INTEGER; attributes : STRING; include_exclude_filter : AGGREGATE OF GENERIC; orderBy : STRING; firstIndex, maxHits : INTEGER; xmlConfigurationName : STRING; resultFileName : STRING; VAR indexOfLastFound : INTEGER; VAR actualHits : INTEGER; VAR queryResultIndex : INTEGER; VAR resultString : STRING) status : INTEGER;
The xpxSelectAggrInstancesEx function searches an aggregate for instances that match a given condition. The condition may be any symbolic Express-X logical expression. An empty string condition will match all aggregate elements.
Each matching aggregate element will be identified by its element index. All the matching elements will generate a row in the query result. The returned query result may contain a single column of element indexes, each identifying an instace that match the logical expression given in the <condition> argument. The attributes of the instances may also be returned in any number of individual columns in the query result table.
The index of the aggregate element from which to start searching for matching instances, and the maximum number of matching element indexes to return, are both specified as input arguments to this procedure. The actual number of matching instances returned and the index of the last returned matching instance element will be returned from the function. This makes it possible to query through huge aggregates by means of a loop where each iteration handles a small subset of the total aggregate. See the example below.
The logical expression given in the <condition> argument will be compiled by the EDMexpressXCompiler. The query will be executed by the EDMexpressVM.
The <attributes> argument may be used to specify which attribute values to return in the query result table. It may contain dot expressions, Express built-in functions and EDMexpressX xpf bult-in functions.
Attributes argument SYNTAX example:
?Name sizeof(sdai_model.underlying_schema.entities)?
This example will return two columns for instances of EDM_MODEL type in the SystemRepository.ExpressDataManager model. The two columns are.
1) The Name attribute of the EDM_MODEL
2) The number of entities in the "underlying schema" of the model.
The column names in the resulting query table will be ?Name? and ?sizeof(sdai_model.underlying_schema.entities)? respectively. Different column names may be specified by using the "->" operator.
Example: if we want the 2nd column to be given the name "Entities", we may write the 2nd attribute like this:
?sizeof(sdai_model.underlying_schema.entities)->Entities?
Note that the characters white space, comma, and semicolon may all be used as delimiters between the attribute names in the <attributes> argument. Hence none of these characters may be used in the attribute name/attribute expression.
The total number of hits will be returned in the <numberOfHits> argument.
The arguments for the function are:
Argument:: | Description: |
aggrId | A numeric aggregateID that uniquely identifies the aggregate of interest in the EDMdatabase. This may be any type of aggregate, persistant, volatile or scratch. |
modelVersion | The version of the edmModel to apply this function call on. The <modelVersion> parameter is a numeric sequence number counting from one by increments of one for each new model version that is created. A zero model version number means the current version. |
condition | A conditional statement, written in Express-X, that the instances shall match. |
options | The options are equivalent to the options used in the EDMinterface function edmiSelectAggrElements except for the XPX prefix |
attributes | Specification of the name and contents of each column of the returned query result table. The following examples illustrate the SYNTAX. |
include_exclude_filter | The numeric id of an aggregate containing the names or ids of the entities that will be affected by this filter. If the option xpxFILTER_AS_ENTITY_IDS is used, this parameter will be interpreted as an aggregate of instance ids, each defining an entity. If the option xpxFILTER_AS_ENTITY_NAMES is used, this parameter will be interpreted as an aggregate containing entity names. If the option xpxINCLUDE_FILTER is used, no instances but those of a type contained in the aggregate will be included. If the option xpxEXCLUDE_FILTER is used, all instances but those of a type contained in the aggregate will be included. |
orderBy | Name of the query result column to use for sorting. The column may be specified by its constructor or by the column title. If the <attributes> argument is: ?DOG.NAME->DOG?, the order by argument may be either ?DOG? or ?DOG.NAME?.This argument is only aplicable when one of the options xpxHTML_FORMAT or xpxASCII_FORMAT is used. Use the options xpxASCENDING and xpxDESCENDING to specify the sorting direction. |
firstIndex | The index of the aggregate element to start searching at. The index of the first element in the actual aggregate will always be index zero, independent of the aggregate type. Hence the legal index range is: 0<= index < number of elements in the aggregate. |
maxHits | Specifies the maximum number of matching instances to return in the <resultString> or in the query result. |
xmlConfigurationName | The name of the XML configuration to apply to the resulting XML formatted query result when the option xpxXML_FORMAT is used. |
resultFileName | The name of the file that will contain the returned XML, HTML or ASCII formatted query result. Only applicable when using the xpxRESULT_IN_FILE option in combination with one of the options xpxHTML_FORMAT, xpxASCII_FORMAT or xpxXML_FORMAT. Use the xpxZIPPED_FILE option to compress the generated file. |
indexOfLastFound | The index of the ?last returned matching element?. This argument enables the caller to search for instances in an incremental way by specifying this returned ?index value plus one? as the input to the next xpxSelectAggrInstancesEx function and so on. |
actualHits | The number of found matching instances. |
queryResultIndex | The index that may be used to identify the queryResult that was generated by the call to this procedure. is used to specify the actual EDMinstanceHashTable. On input : queryResultIndex = 0 : the resulting instances will be inserted in a new EDMinstanceHashTable. queryResultIndex != 0: Specifies an actual existing EDMinstanceHashTable, i.e., the resulting instances will be inserted (added) to the specified EDMinstanceHashTable On return: queryResultIndex : The actual EDMinstanceHashTable index that holds the resulting instances. |
resultString | Variable that will receive the returned XML formatted query result when the options xpxRESULT_IN_STRING and xpxXML_FORMAT are used. |
Option: | Description: |
xpxALL_ATTRIBUTES | When the argument <attributes> is unset or an empty string, all attributes of the instances will be included in the query result. However, if the <attributes> argument is used to add one or more aditional constructed columns or to rename a column in the query result, the return of all the instance attributes will be hindered due to an <attributes> argument that is no longer unset or an empty string. Use this option to force the including of all instance attributes even when the <attributes> argument is not unset or an empty string. |
xpxINCLUDE_CONFIGURATION | Includes the XML Configuration in the generated ISO10303-28 compliant XML formatted query result. This option has no effect unless combined with the option xpxXML_FORMAT |
xpxINCLUDE_SCHEMA | Includes the underlying meta data in the generated ISO10303-28 compliant XML formatted query result. This option has no effect unless combined with the option xpxXML_FORMAT. |
xpxRESULT_IN_STRING | The resulting table will be returned in a string. Must be used in combination with xpxXML_FORMAT |
xpxEXTRACT_SHALLOW | Use this option to force a shallow XML formatted query result. ISO10303-28 compliant XML Query results are deep by default. No other query result format supported by this function is deep. Hence, this option has no effect unless combined with the option xpxXML_FORMAT. |
xpxTRANSFER_NO_DATA | No actual query result will be returned. Use this option when the number of matching elements is the only information needed or for testing the query SYNTAX before actually performing it. |
xpxASCENDING | Arrange the query result in ascending order. This option is only applicable when the <orderBy> argument is used. |
xpxDESCENDING | Arrange the query result in descending order. This option is only applicable when the <orderBy> argument is used. |
xpxONLY_INSTANCE_IDS | Return only a single column with the instanceIds of the matcing instances. |
xpxINCLUDE_INSTANCE_IDS | Prepend all attribute columns in the query result with an instanceId column. |
xpxINCLUDE_FILTER | Only the aggregate elements of types that are explicitely listed in the <include_exclude_filter> argument will be checked. |
xpxEXCLUDE_FILTER | All the aggregate elements, but those of types that are explicitely listed in the <include_exclude_filter> argument, will be checked. |
xpxRESULT_IN_FILE | The resulting table will be written to a file on the local file system of the calling application. The name of the file must be specified in the <resultFileName> argument. |
xpxEDM_IDENTIFIERS | The instanceIds that uniquely identify the instances in EDMdatabase will be used as xmlIds for identification of the instances within the ISO10303-28 compliant XML formatted query result. |
xpxFILTER_AS_ENTITY_NAMES | The <include_exclude_filter> argument will be interpreted as an aggregate of entity names. |
xpxFILTER_AS_ENTITY_IDS | The <include_exclude_filter> argument will be interpreted as an aggregate of entityIds. |
xpxHTML_FORMAT | The query result table will be written to an HTML formatted file on the local file system. |
xpxASCII_FORMAT | The query result table will be written to a plain ASCII formatted file on the local file system. |
xpxONLY_ELEMENT_INDEXES | The query result table will contain only one column with the index of all the matching elements. |
xpxOLD_XML_FORMAT | The result of the query will be written to a simple wellformed XML formatted file on the local file system. |
xpxXML_FORMAT | The result of the query will be returned in an ISO10303-28 compliant XML formatted string or in a file on the local file system. |
xpxZIPPED_FILE | The file given by the argument <resultFileName> will be compressed with gzip. This option has no effect unless combined with the option [xpxRESULT_IN_FILE]. |
xpxIGNORE_EMPTY_COLUMNS | Columns for attributes that do not have defined values for any of the returned instances will be left out of the query result table. |
| xpxRESULT_IN_INSTANCE_HASH_TABLE | insert the resulting instances in an EDMinstanceHashTable |
Example:
. . .
firstIndex = 1;
maxHits := 10;
actualHits := maxHits;
WHEN (actualHits = maxHits);
BEGIN
stat := xpxSelectAggrInstancesEx (myAggrId, 0,
?SELF.WIFE.FIRST_NAME LIKE Lucy?,
xpxRESULT_IN_STRING + xpxASCENDING,
?FirstName, LastName, Address?, 0, ?LastName?,
firstIndex, maxHits, ??, ??, lastFound, actualHits,
0, resultString);
(* Process the result string here *)
firstIndex := lastMatch + 1;
END;
. . .