Class SybasePkGenerator

java.lang.Object
org.apache.cayenne.dba.JdbcPkGenerator
org.apache.cayenne.dba.sybase.SybasePkGenerator
All Implemented Interfaces:
PkGenerator

public class SybasePkGenerator
extends JdbcPkGenerator
Primary key generator implementation for Sybase. Uses a lookup table named "AUTO_PK_SUPPORT" and a stored procedure "auto_pk_for_table" to search and increment primary keys for tables.
  • Constructor Details

    • SybasePkGenerator

      public SybasePkGenerator()
      Used by DI
      Since:
      4.1
    • SybasePkGenerator

      protected SybasePkGenerator​(JdbcAdapter adapter)
  • Method Details

    • pkTableCreateString

      protected String pkTableCreateString()
      Overrides:
      pkTableCreateString in class JdbcPkGenerator
    • createAutoPk

      public void createAutoPk​(DataNode node, List<DbEntity> dbEntities) throws Exception
      Generates database objects to provide automatic primary key support. Method will execute the following SQL statements:

      1. Executed only if a corresponding table does not exist in the database.

          CREATE TABLE AUTO_PK_SUPPORT (
             TABLE_NAME VARCHAR(32) NOT NULL,
             NEXT_ID DECIMAL(19,0) NOT NULL
          )
       

      2. Executed under any circumstances.

       if exists (SELECT * FROM sysobjects WHERE name = 'auto_pk_for_table')
       BEGIN
          DROP PROCEDURE auto_pk_for_table 
       END
       

      3. Executed under any circumstances.

      CREATE PROCEDURE auto_pk_for_table
       @tname VARCHAR(32),
       @pkbatchsize INT AS BEGIN BEGIN TRANSACTION UPDATE AUTO_PK_SUPPORT set NEXT_ID =
                    NEXT_ID +
       @pkbatchsize WHERE TABLE_NAME =
       @tname SELECT NEXT_ID from AUTO_PK_SUPPORT where NEXT_ID =
       @tname COMMIT END
       
      Specified by:
      createAutoPk in interface PkGenerator
      Overrides:
      createAutoPk in class JdbcPkGenerator
      Parameters:
      node - node that provides access to a DataSource.
      dbEntities - a list of entities that require primary key auto-generation support
      Throws:
      Exception
    • createAutoPkStatements

      public List<String> createAutoPkStatements​(List<DbEntity> dbEntities)
      Description copied from interface: PkGenerator
      Returns a list of SQL strings needed to generates database objects to provide automatic primary support for the list of entities. No actual database operations are performed.
      Specified by:
      createAutoPkStatements in interface PkGenerator
      Overrides:
      createAutoPkStatements in class JdbcPkGenerator
    • dropAutoPk

      public void dropAutoPk​(DataNode node, List<DbEntity> dbEntities) throws Exception
      Drops database objects related to automatic primary key support. Method will execute the following SQL statements:
       if exists (SELECT * FROM sysobjects WHERE name = 'AUTO_PK_SUPPORT')
       BEGIN
          DROP TABLE AUTO_PK_SUPPORT
       END
       
       
       if exists (SELECT * FROM sysobjects WHERE name = 'auto_pk_for_table')
       BEGIN
          DROP PROCEDURE auto_pk_for_table 
       END
       
      Specified by:
      dropAutoPk in interface PkGenerator
      Overrides:
      dropAutoPk in class JdbcPkGenerator
      Parameters:
      node - node that provides access to a DataSource.
      dbEntities - a list of entities whose primary key auto-generation support should be dropped.
      Throws:
      Exception
    • dropAutoPkStatements

      public List<String> dropAutoPkStatements​(List<DbEntity> dbEntities)
      Description copied from interface: PkGenerator
      Returns SQL string needed to drop database objects associated with automatic primary key generation. No actual database operations are performed.
      Specified by:
      dropAutoPkStatements in interface PkGenerator
      Overrides:
      dropAutoPkStatements in class JdbcPkGenerator
    • longPkFromDatabase

      protected long longPkFromDatabase​(DataNode node, DbEntity entity) throws Exception
      Description copied from class: JdbcPkGenerator
      Performs primary key generation ignoring cache. Generates a range of primary keys as specified by "pkCacheSize" bean property.

      This method is called internally from "generatePkForDbEntity" and then generated range of key values is saved in cache for performance. Subclasses that implement different primary key generation solutions should override this method, not "generatePkForDbEntity".

      Overrides:
      longPkFromDatabase in class JdbcPkGenerator
      Throws:
      Exception
      Since:
      3.0