Package com.orchestranetworks.query

Interface Query<T>

public interface Query<T>
An object that represents a compiled and validated SQL query.

A query is executed by calling the method getResult().

Note that this class is not thread-safe.

Since:
6.0.0
See Also:

  • Method Summary

    Modifier and Type
    Method
    Description
    String
    explain()
    Returns a meaningful string representation of the query plan that is used to compute the result of this query.
    QueryResult<T>
    getResult()
    Executes the query on the registered dataset(s), and returns a result object, ready to iterate.
    void
    setFetchSize(int rows)
    Provides a hint to the underlying database with the number of records to fetch at a time from the result of executing this query.
    void
    setIncludeOcculting(boolean includeOcculting)
    Sets whether or not the query must consider records in occulting mode.
    void
    setLocale(Locale aLocale)
    Sets a locale to the query.
    void
    setParameter(int aPosition, Object aValue)
    Sets a value to a positional parameter in the query.
    void
    setSession(Session aSession)
    Sets the user session on the query.

  • Method Details

    • getResult

      QueryResult<T> getResult() throws QueryPermissionException
      Executes the query on the registered dataset(s), and returns a result object, ready to iterate.

      In terms of isolation, when the result object gets iterated, it is guaranteed that all internal persistence and indexing entities used in this process will utilize the same snapshot (the one at the moment the current method was executed).

      Throws:
      QueryPermissionException - if a session is provided and at least one forbidden node is used in the request.

    • explain

      String explain()
      Returns a meaningful string representation of the query plan that is used to compute the result of this query.

    • setSession

      void setSession(Session aSession)
      Sets the user session on the query. This activates the permission checks and sets the session locale.

      Applying the permissions checks will have the following effects:

      • the records will be filtered using the access rules on records and scripted access rules, if any;
      • a QueryPermissionException will be thrown on execution if at least one forbidden node is used in the query. Currently, this does not take into account record-dependent access rules set on fields.
      See Also:

    • setLocale

      void setLocale(Locale aLocale)
      Sets a locale to the query.
      See Also:

    • setParameter

      void setParameter(int aPosition, Object aValue)
      Sets a value to a positional parameter in the query.

      A parameter is represented by a question mark ('?') in the query. The first position is 0: 

       
   Query<Tuple> query = dataset.createQuery("SELECT * FROM customer WHERE age = ? AND name = ?");
   query.setParameter(0, 42);
   query.setParameter(1, "John");

      The type of the specified value should match the type of the parameter. See Sql Mapping of data types for more information.

      See Also:

    • setFetchSize

      void setFetchSize(int rows)
      Provides a hint to the underlying database with the number of records to fetch at a time from the result of executing this query. If the fetch size specified is '0', the underlying implementation determines the fetch size independently.

      See Setting a fetch size for the limitations when using PostgreSQL as the underlying database.

      Parameters:
      rows - the number of rows to fetch
      See Also:

    • setIncludeOcculting

      void setIncludeOcculting(boolean includeOcculting)
      Sets whether or not the query must consider records in occulting mode.

      By default, these records are ignored.

      See Also: