com.ibm.db2os390.ive.da
Class DB2VisualExplain

java.lang.Object
  |
  +--com.ibm.db2os390.ive.da.DB2VisualExplain

public class DB2VisualExplain

extends java.lang.Object

DB2VisualExplain is a class to provide all external APIs which used by Visual Explain for DB2/zOS.

genXMLDynamic:
This API retrieves information from DB2/zOS system catalog tables and explain tables and to publish the desired information used by IVE in XML format.
It does the following things:
Issues the explain statement to DB2/zOS;
Retrieves the information from system catalog tables and explain tables regarding to the explain statement;
Generates the desired information by Visual Explain in XML format.

genXMLStatic:
This API retrieves information from DB2/zOS system catalog tables and explain tables and to publish the desired information used by IVE in XML format.
It does the following things:
Retrieves the information from system catalog tables and explain tables regarding to the explain statement;
Generates the desired information by Visual Explain in XML format.

enable:
This API creates the DB2/zOS runtime environment for Visual Explain.
It does the following things:
Checks if there is any existing table with the same name as the explain tables, if so, check the table format;
Migrates explain tables with v7 format to v8 format;
Creates those explain tables under the given schema which will be used by Visual Expalin;
Creates indexes against explain tables.

delete:
This API helps user to maintain size of explain tables.
It does the following things:
Deletes obsolete data which specified by user from explain tables.

migarte:
This API migrates v7 explain tables to V8 format for IVE.
It does the following things:
Creates a bakup explain table to store all data in V7 table;
Migrates v7 table to v8 format.

repair:
This API repairs the DB2/zOS runtime environment for Visual Explain.
It does the following things:
Recreates the missing explain table.

Constructor Summary

DB2VisualExplain()

Method Summary

static void	delete(java.sql.Connection con, java.lang.String sqlid, java.lang.String creator_name, java.sql.Timestamp timestamp, int[] error_code, java.lang.String[] error_token) Delete some data in explain tables, which is older than specified timestamp.
static void	enable(java.sql.Connection con, java.lang.String sqlid, java.lang.String creator_name, java.lang.String db_name, java.lang.String ts_name, int[] error_code, java.lang.String[] error_token) Creates all explain tables under the given schema name.
static void	genXMLDynamic(java.sql.Connection con, java.lang.String sqlid, int queryno, java.lang.String sql, int degree, java.lang.String[] xml, int[] error_code, java.lang.String[] error_token) Explains a dynamic SQL query, retrieves information from catalog and explain tables, generates access path and correponding information in XML string format.
static void	genXMLStatic(java.sql.Connection con, java.lang.String sqlid, int queryno, java.lang.String sql, java.lang.String applname, java.lang.String progname, java.lang.String collid, java.lang.String version, java.sql.Timestamp timestamp, java.lang.String[] xml, int[] error_code, java.lang.String[] error_token) Retrieves information from catalog and explain tables for a static SQL query, generates access path and correponding information in XML string format.
static void	migrate(java.sql.Connection con, java.lang.String sqlid, java.lang.String creator_name, java.lang.String db_name, java.lang.String ts_name, java.lang.String tname, int[] error_code, java.lang.String[] error_token) Migrate those v7 explain tables under the given schema which are used by IVE.
static void	repair(java.sql.Connection con, java.lang.String sqlid, java.lang.String db_name, java.lang.String ts_name, java.lang.String tname, int[] error_code, java.lang.String[] error_token) Repairs those explain tables under the given schema which are used by IVE.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DB2VisualExplain

public DB2VisualExplain()

Method Detail

enable

public static void enable(java.sql.Connection con,
                          java.lang.String sqlid,
                          java.lang.String creator_name,
                          java.lang.String db_name,
                          java.lang.String ts_name,
                          int[] error_code,
                          java.lang.String[] error_token)

Creates all explain tables under the given schema name.

Parameters:

con - a database connection

sqlid - current sqlid

creator_name - the schema name under which the user intends to create explain tables

db_name - the database name, the default is DSNDB04

ts_name - the tablespace name, the default is the first 8 characters of the creating table names

error_code - stores the error code returned, only the first entry of the array is used

error_token - stores the detailed error information returned, only the first entry of the array is used

delete

public static void delete(java.sql.Connection con,
                          java.lang.String sqlid,
                          java.lang.String creator_name,
                          java.sql.Timestamp timestamp,
                          int[] error_code,
                          java.lang.String[] error_token)

Delete some data in explain tables, which is older than specified timestamp.

Parameters:

con - a database connection

sqlid - current sqlid

creator_name - the schema name under which the user intends to create explain tables

timestamp - user specified timestamp, DeleteIVE will delete all data older than this timestamp

error_code - stores the error code returned, only the first entry of the array is used

error_token - stores the detailed error information returned, only the first entry of the array is used

migrate

public static void migrate(java.sql.Connection con,
                           java.lang.String sqlid,
                           java.lang.String creator_name,
                           java.lang.String db_name,
                           java.lang.String ts_name,
                           java.lang.String tname,
                           int[] error_code,
                           java.lang.String[] error_token)

Migrate those v7 explain tables under the given schema which are used by IVE.

Parameters:

con - a database connection

sqlid - current sqlid

creator_name - the schema name under which the user intends to create explain tables

db_name - the database name, the default is DSNDB04

ts_name - the tablespace name, the default is the first 8 characters of the creating table names

tname - the name of the table to be migrated

error_code - stores the error code returned, only the first entry of the array is used

error_token - stores the detailed error information returned, only the first entry of the array is used

repair

public static void repair(java.sql.Connection con,
                          java.lang.String sqlid,
                          java.lang.String db_name,
                          java.lang.String ts_name,
                          java.lang.String tname,
                          int[] error_code,
                          java.lang.String[] error_token)

Repairs those explain tables under the given schema which are used by IVE.

Parameters:

con - a database connection

sqlid - the schema name under which the explain table is created

db_name - the database name, the default is DSNDB04

ts_name - the tablespace name

tname - the name of the table to be repaired

error_code - stores the error code returned, only the first entry of the array is used

error_token - stores the detailed error information returned, only the first entry of the array is used

genXMLDynamic

public static void genXMLDynamic(java.sql.Connection con,
                                 java.lang.String sqlid,
                                 int queryno,
                                 java.lang.String sql,
                                 int degree,
                                 java.lang.String[] xml,
                                 int[] error_code,
                                 java.lang.String[] error_token)

Explains a dynamic SQL query, retrieves information from catalog and explain tables, generates access path and correponding information in XML string format.

Parameters:

con - a database connection

sqlid - the schema name under which the explain tables are created

queryno - a number to identify the SQL query being explained

sql - the dynamic SQL query need to explained

degree - the degree number to be set

xml - stores the XML string representing access path and other corresponding information

error_code - stores the error code returned, only the first entry of the array is used

error_token - stores the detailed error information returned, only the first entry of the array is used

genXMLStatic

public static void genXMLStatic(java.sql.Connection con,
                                java.lang.String sqlid,
                                int queryno,
                                java.lang.String sql,
                                java.lang.String applname,
                                java.lang.String progname,
                                java.lang.String collid,
                                java.lang.String version,
                                java.sql.Timestamp timestamp,
                                java.lang.String[] xml,
                                int[] error_code,
                                java.lang.String[] error_token)

Retrieves information from catalog and explain tables for a static SQL query, generates access path and correponding information in XML string format.

Parameters:

con - a database connection

sqlid - the schema name under which the explain tables are created

queryno - a number to identify the SQL query being explained

sql - the SQL statement stored in SYSIBM.SYSSTMT table

applname - the name of the application plan

progname - the name of the program or package containg the query being explained

collid - collection identifier

version - the package version

timestamp - the explain time

xml - stores the XML string representing access path and other corresponding information, only the first entry of the array is used

error_code - stores the error code returned, only the first entry of the array is used

error_token - stores the detailed error information returned, only the first entry of the array is used