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PostgreSQL Install-Windows

without comments

A number of folks have asked me to create a post of a PostgreSQL installation on Windows. So, here is my step-by-step PostgreSQL 9.3 installation.

Download PostgreSQL Database

You can start the download of PostgreSQL from this site. It leads you to the EnterpriseDB site, where you can download the prepackaged software.

Install PostgreSQL 9.3 on Windows

These steps walk you through installing PostgreSQL and the the pgJDBC v9.3, psqlODBC (32 bit), and psqlODBC (64 bit) packages.

PostgreSQL_i01

  1. The first thing you need to do is launch the PostgreSQL file from download folder.

PostgreSQL_i02

  1. After launching the downloaded file, you see an Open File – Security Warning dialog message. Click the Run button to run the PostgreSQL executable file.

PostgreSQL_i03

  1. The first dialog screen is the Setup – PostgreSQL dialog, which welcomes you and prompts you to start the installtion of PostgreSQL. Click the Next button to continue.

PostgreSQL_i04

  1. The Installation Directory dialog sets the location for the PostgreSQL server. Click the Next button to continue.

PostgreSQL_i05

  1. The Data Directory dialog sets the location for the PostgreSQL server’s data repository. Click the Next button to continue.

PostgreSQL_i06

  1. The first Setup dialog sets the database’s superuser password. Click the Next button to continue.

PostgreSQL_i07

  1. The second Setup dialog sets the database’s listener port, which is Port 5432 by default. Click the Next button to continue.

PostgreSQL_i08

  1. The third Setup dialog sets the database’s default Locale. Click the Next button to continue.

PostgreSQL_i09

  1. The Ready to Install dialog lets you start the installation. Click the Next button to continue.

PostgreSQL_i10

  1. The Installing dialog lets you montor the unpacking of programs for the installation. You need not click any buttons to continue.

PostgreSQL_i11

  1. The Completing the PostgreSQL Setup Wizard dialog advises you that you’ve completed the setup. Checking the Stack Builder check box lets you download and install additional tools, drivers, and applications. Click the Next button to continue.

PostgreSQL_i12

  1. This is Welcome dialog to the Stack Builder. Click the Next button to continue.

PostgreSQL_i13

  1. This is dialog lets you select applications that you would like to install. Click the plus symbol for the Database Drivers option to continue.

PostgreSQL_i14

  1. In the modified dialog, click the pgJDBC v9.3, psqlODBC (32 bit), and psqlODBC (64 bit) check boxes. Then, click the Next button to continue.

PostgreSQL_i15

  1. This dialog tells you the pgJDBC v9.3, psqlODBC (32 bit), and psqlODBC (64 bit) installed packages. Click the Next button to continue.

PostgreSQL_i16

  1. This dialog lays a downloading progress bar while loading the additional packages. You don’t need to do anything to continue.

PostgreSQL_i17

  1. This dialog lays a downloading progress bar while loading the additional packages. Click the Next button to continue.

PostgreSQL_i18

  1. The Setup pgJDBC dialog welcomes you to the setup wizard. Click the Next button to continue.

PostgreSQL_i19

  1. The Installation Directory dialog lets you set the pgJDBC installation directory. Click the Next button to continue.

PostgreSQL_i20

  1. The Ready to Install dialog lets you install the pgJDBC package. Click the Next button to install it.

PostgreSQL_i21

  1. The Setup dialog confirms you’ve installed the add-on packages. Click the Finish button to complete the installation.

Configure psqlODBC on Windows

These steps walk you through configuring the psqlODBC packages.

PostgreSQL_i22

  1. The Setup dialog helps you configure the psqlODBC package. Click the Next button to install it.

PostgreSQL_i23

  1. The Installation Directory dialog lets you set the psqlODBC installation directory. Click the Next button to continue.

PostgreSQL_i23

  1. The Ready to Install dialog lets you install the psqlODBC package. Click the Next button to install it.

PostgreSQL_i24

  1. The Ready to Install dialog lets you install the psqlODBC package. Click the Next button to install it.

PostgreSQL_i25

  1. The Installing psqlODBC dialog displays a dialog while installing the psqlODBC package(s). You need not click anything, the dialog dismisses itself when complete.

PostgreSQL_i26

  1. The Installing psqlODBC dialog displays a dialog while installing the psqlODBC package(s). You need not click anything, the dialog dismisses itself when complete.

PostgreSQL_i27

  1. The Stack Builder dialog displays a message that everything is installed. Click the Finish button when complete.

Connect to the Default PostgreSQL database

You have two options for connecting to the PostgreSQL database. One uses the GUI pgAdmin III console and the other uses the command line.

Connect through pgAdmin III to the PostgreSQL Database

PostgreSQL_i27

  1. In Windows, navigate to through the Start to the pgAdmin III menu option.

PostgreSQL_i28

  1. After launching pgAdmin III, you’ll see the pgAdmin II console, displayed at left.

PostgreSQL_i29

  1. Right click on the PostgreSQL 9.3 (localhost:5432) item in the Object browser and click the Connect menu choice from the floating menu.

PostgreSQL_i30

  1. Enter the password you chose when installing the PostgreSQL Server, and click the OK button.

Connect through the Command-line to the PostgreSQL Database

These steps show you how to connect through the PostgreSQL Command Line Interface (CLI) – psql. psql is like Oracle’s sqlplus, MySQL’s mysql, and Microsoft SQL Server’s sqlcmd CLI interfaces. By default, the PostgreSQL binary directory is not in your default %PATH% environment variable, so you need to add it. I recommend an environment file because in a test situation you may not want to use it all the time.

Create the following directory for the environment file:

C:\Data\PostgreSQL\env

You can create an environment file with any text editor or do it at the command line, like this:

COPY CON postgresqlenv.bat
SET PATH=%PATH%;C:\Program Files\PostgreSQL\9.3\bin;.
^Z

Then, you can source the environment file like this:

C:\> postgresql.bat

Now, you can connect to the default database provided you understand that PostgreSQL Stack Builder set some values that differ from the defaults if you installed it manually. Specifically, they set the default value of the database to postgres and default value of the user to postgres.

That means you can connect with the following, provided you remember the password you used during installation:

C:\> psql -d postgres -U postgres

You should see the following when you connect:

C:\> psql -d postgres -U postgres
 Password for user postgres:
psql (9.3.3)
WARNING: Console code page (437) differs from Windows code page (1252)
         8-bit characters might not work correctly. See psql reference
         page "Notes for Windows users" for details.
Type "help" for help.

You can now submit interactive SQL statements or run batch files, like:

postgres=# SELECT 'Hello World!';

It displays:

   ?COLUMN?
--------------
 Hello World!
(1 ROW)

Adding a column alias to the string literal gives a more readable formatted output:

postgres=# SELECT 'Hello World!' AS "String Literal";

It displays:

 String Literal
----------------
 Hello World!
(1 ROW)

PostgreSQL’s CLI Help

You have the ability to do a lot with the PostgreSQL psql CLI. The general command to discover help is help, and it displays the following:

postgres=# help
You are USING psql, the command-line interface TO PostgreSQL.
TYPE:  \copyright FOR distribution terms
       \h FOR help WITH SQL commands
       \? FOR help WITH psql commands
       \g OR terminate WITH semicolon TO EXECUTE query
       \q TO quit

You quit PostgreSQL with a \q command:

postgres=# \q

Have fun exploring PostgreSQL. As always, I hope this helps those looking to discover how to install and use PostgreSQL.

Written by maclochlainn

March 2nd, 2014 at 7:59 pm

Add User Defined Types

with one comment

Somebody asked me if there was a cheaper alternative to using the Embarcadero Data Architect (a data modeling tool). I said sure, you can use the MySQL Workbench. My friend laughed and said, it’s to model Oracle databases and they use different data types. I broke the news to him that he can create his own user defined types and use MySQL Workbench to model problems for the Oracle Database 11g.

For example, you can launch the MySQL Workbench, and click on the Model menu option, and in the menu window click on the User Defined Types choice, as shown in the following:

UserDefinedType

Choosing the User Defined Type option, launches the following form. You can enter customized user defined types in the User Defined Types module:

MySQLWB_UserDefinedTypes01

You enter user defined types by entering a name value and choosing valid MySQL type value before clicking the Add button. When you’ve added your last user defined type, click the OK button instead of the Add button. The next screen shot shows how you can create Oracle Database 11g native data types, specifically the NUMBER and VARCHAR2 data types.

MySQLWB_UserDefinedTypes02

Hopefully, this has shown that you can create User Defined Types let you use MySQL Workbench to create Oracle ERD models. Here’s an example of a table with Oracle’s NUMBER and VARCHAR2 data types:

CustomGLTable

Yes, MySQL Workbench is a marvelous tool with wide potential for use to solve problems with MySQL and other databases.

Written by maclochlainn

February 28th, 2014 at 2:03 am

Relationship Notations

without comments

One of my students asked how to convert MySQL Workbench’s default Crow’s Foot (IE) diagram to one of the other supported formats – Classic, Connect to Columns, UML, and IDEF1X. Crow’s Foot is also known as the Information Engineering Model method (covered in Chapter 3 of my MySQL Workbench: Data Modeling & Development.

It quite simple, you open the Model Overview window, click on the Model menu choice. In the dialog, click on the Relationship Notation menu option. Click on one of the choices in the nested menu, like Column to Columns.

ModifyRelationNotations

Hope this helps those working with MySQL Workbench.

Written by maclochlainn

February 27th, 2014 at 1:22 am

MySQL Image Architecture

with 14 comments

The LinkedIn MySQL DB Development group posed a questions on how to handle images. Naturally, the argument always goes: Should images be deployed in the database or the file system? I believe they should be stored in the database because the cost and time associated is too high with regard to managing files, a file naming schema, and backing up the file system discretely from the database.

Since there’s a significant difference between the backup of transactional data and image data, they should be placed in different databases. The imagedb database is where you would place the images and large text descriptions, as shown in the MySQL Workbench ERD:

imagedb ERD

The imagedb ERD splits the foreign key references back to the system_user table, which contains the individual user credentials. The system_user table serves as the Access Control List (ACL) for the application.

Until I get a chance to write the code for this model, you can refer to the generic PHP/MySQL solution from several years back (its code source was last tested with PHP 5.3). As always, I hope this helps.

Written by maclochlainn

February 23rd, 2014 at 2:02 am

Drop Types Recursively

with one comment

As covered in my new Oracle Database 12c PL/SQL Programming book (publisher’s satisfied), you can evolve object types. That means you can change a base object type and the change cascades through dependents. Somebody asked how to remove an object type chain without appending the FORCE clause.

It’s quite easy if you understand writing a recursive function in PL/SQL, as done here:

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-- Create a recursive function.
CREATE OR REPLACE
  FUNCTION drop_dependents
  (pv_base_object_type  VARCHAR2) RETURN NUMBER IS
 
  /* Declare a return data type. */
  lv_retval  NUMBER := 0;
 
  /* Declare item type. */
  lv_type_name    VARCHAR2(30);
  lv_object_name  VARCHAR2(30);
 
  /* The first part of the cursor finds the dependent type names of complex object 
     types, and the second part of the cursor finds the dependent collection types.
     Effectively the set operator finds two distinct branches because you may use
     any base type as an element of a complex object or of a collection. */
  CURSOR base_type 
  (cv_base_type  VARCHAR2) IS
    SELECT   uta.type_name
    ,        NULL AS object_name
    FROM     user_type_attrs uta INNER JOIN user_types ut
    ON       uta.attr_type_name = ut.type_name
    WHERE    ut.type_name = cv_base_type
    UNION ALL
    SELECT   uct.type_name
    ,        NULL AS object_name
    FROM     user_types ut INNER JOIN user_coll_types uct
    ON       ut.type_name = uct.elem_type_name
    WHERE    uct.elem_type_name = cv_base_type
    UNION ALL
    SELECT   CASE
               WHEN package_name IS NULL THEN
                 uo.object_type
               ELSE
                 'PACKAGE'
             END AS type_name
    ,        CASE
               WHEN package_name IS NULL THEN
                 ua.object_name
               ELSE
                 ua.package_name
             END AS object_name
    FROM     user_arguments ua LEFT JOIN user_objects uo
    ON       ua.package_name = uo.object_name
    OR       ua.object_name = uo.object_name
    WHERE    type_name = cv_base_type;
 
BEGIN
 
  /* Open a parameterized cursor. */  
  OPEN  base_type(pv_base_object_type);
 
  /* Loop through return records. */
  LOOP
    /* Fetch records. */
    FETCH base_type
    INTO  lv_type_name
    ,     lv_object_name;
 
    /* Drop type without dependents, or drop leaf node dependent. */
    IF base_type%NOTFOUND THEN
 
      /* Drop functions when they include an object type or object type
         dependent as a formal parameter type or return type. Drop
         procedures when they include an object type or object type
         dependent. Drop procedures when any function or procedure
         uses an object type or object type dependent. */
      IF lv_type_name IN ('FUNCTION','PACKAGE','PROCEDURE') THEN
 
        /* Drop the base type when no dependents are found. */
        EXECUTE IMMEDIATE 'DROP '||lv_type_name||' '||lv_object_name;
 
      ELSE
 
        /* Drop the base type when no dependents are found. */
        EXECUTE IMMEDIATE 'DROP TYPE '||pv_base_object_type;
 
      END IF;
 
      /* Set exit state to one or true. */
      lv_retval := 1;
 
      /* Exit the loop. */
      EXIT;
 
    ELSE
 
      /* A type must exclude function, package, and procedure; and the
         object name must be null before you recurse to another level. */
      IF lv_type_name NOT IN ('FUNCTION','PACKAGE','PROCEDURE') AND
         lv_object_name IS NOT NULL THEN
 
        /* Drop base type when no dependents are found. */
        lv_retval := drop_dependents(lv_type_name);
 
      END IF;
 
    END IF;
  END LOOP;
 
  /* Close open cursor. */
  CLOSE base_type;
 
  /* Return 0 for false. */
  RETURN lv_retval;
END;
/

Somebody asked me to provide a test case of a hierarchy of object types to support the drop_dependents function. So, here’s the test case code:

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-- Create object type.
CREATE OR REPLACE 
  TYPE item_object IS OBJECT
  ( item_name     VARCHAR2(30)
  , item_subname  VARCHAR2(30));
/
 
-- Create object type.
CREATE OR REPLACE 
  TYPE identified_object IS OBJECT
  ( identified_id      NUMBER
  , identified_object  item_object);
/
 
-- Create object collection.
CREATE OR REPLACE
  TYPE item_table IS TABLE OF item_object;
/
 
-- Create object collection.
CREATE OR REPLACE
  TYPE item_varray IS VARRAY(5) OF item_object;
/
 
-- Create object type.
CREATE OR REPLACE 
  TYPE item_async_table IS OBJECT
  ( item_name        VARCHAR2(30)
  , item_collection  item_table);
/
 
-- Create object type.
CREATE OR REPLACE 
  TYPE item_async_varray IS OBJECT
  ( item_name        VARCHAR2(30)
  , item_collection  item_varray);
/
 
-- Create object collection.
CREATE OR REPLACE
  TYPE item_list IS TABLE OF item_async_table;
/
 
-- Create object collection.
CREATE OR REPLACE
  TYPE item_array IS VARRAY(10) OF item_async_varray;
/
 
-- Create package specification.
CREATE OR REPLACE PACKAGE item_package AS
 
  /* A published function of the package. */
  FUNCTION initialize_object
  ( id    NUMBER
  , name  NUMBER ) RETURN ITEM_OBJECT;
 
END item_package;
/
 
-- Create a schema function.
CREATE OR REPLACE FUNCTION get_item_object
  ( pv_id    NUMBER
  , pv_name  NUMBER ) RETURN ITEM_OBJECT IS
 
  /* Declare a local variable. */
  lv_item_object   ITEM_OBJECT;
 
BEGIN
 
  /* Initialize the object type. */
  lv_item_object := item_object(pv_id, pv_name);  
 
  /* Return the dat type. */
  RETURN lv_item_object;
END;
/

If you call the function with the base type, it’ll drop the most dependent object type first, and the base object type last. The rest are dropped in their order of dependency. You can call a drop_dependents function with a base type, like ITEM_OBJECT, by using the following syntax:

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SET SERVEROUTPUT ON SIZE UNLIMITED
BEGIN
  IF drop_dependents('ITEM_OBJECT') = 1 THEN
    dbms_output.put_line('Objects dropped.');
  END IF;
END;
/

Hope this helps those looking to drop a chain of object types in an Oracle database.

Written by maclochlainn

February 18th, 2014 at 3:39 am

Signal from a procedure

without comments

As I review with my students, a stored function works like a standalone program, while a stored procedure runs in the scope of another program unit. For example, you can compare the result of a function as an expression in an IF statement, like:

  IF add_numbers(1,3) > 3 THEN
    ...
  ELSE
    ...
  END IF;

You can’t call procedures inside an IF statement, but you can call the procedure and use a single OUT-mode (pass-by-reference) parameter from the procedure in a subsequent IF statement. You can implement a a wait procedure like that with the following example.

The example first creates two tables, the road_runner and coyote tables:

-- Drop road_runner table if exists.
DROP TABLE IF EXISTS road_runner;
 
-- Create roadrunner table.
CREATE TABLE road_runner
( road_runner_id    int unsigned  auto_increment primary key
, road_runner_text  varchar(20)
, CONSTRAINT road_runner_nk UNIQUE (road_runner_text));
 
-- Drop coyote table if exists.
DROP TABLE IF EXISTS coyote;
 
-- Create coyote table.
CREATE TABLE coyote
( coyote_id       int unsigned  auto_increment primary key
, coyote_text     varchar(20)
, road_runner_id  int unsigned
, CONSTRAINT coyote_nk UNIQUE (coyote_text));

The following creates a procedure that:

  • Writes data to two tables when the values are unique, returning a value of zero when it works.
  • Writes data to neither table when the values to either table are non-unique, returning a value of one when it fails.

The procedure uses a 0 as a false value and a 1 as a true value. The use of a 0 and 1 for truth is a consistent approach for languages where they don’t support a Boolean data type.

-- Change the delimiter to a "$$"
DELIMITER $$
 
-- Drop the paired procedure.
DROP PROCEDURE IF EXISTS two_table$$
 
-- Create the paired procedure.
CREATE PROCEDURE two_table
(IN    pv_road_runner_text  varchar(20)
,IN    pv_coyote_text       varchar(20)
,  OUT pv_confirm_it        int)
BEGIN
  /* Declare a variable to hold a sequence value for an 
     auto incrementing value. */
  DECLARE lv_road_runner_id  int unsigned;
 
  /* Declare a condition variable for attempting to write
     a non-unique record to a table. */
  DECLARE duplicate CONDITION FOR 1062;
 
  /* Declare an event handler for a duplicate condition 
     variable, rollback transaction, and set 1 as a false
     condition. */
  DECLARE EXIT HANDLER FOR duplicate
    BEGIN
      ROLLBACK to all_or_none;
      SET pv_confirm_it = 1;
    END;
 
  /* Start the transaction. */
  START TRANSACTION;
 
  /* Set the save point for a multiple table transaction. */
  SAVEPOINT all_or_none;
 
  /* Insert into road runner table. */
  INSERT INTO road_runner
  (road_runner_text)
  VALUES  
  (pv_road_runner_text);
 
  /* Capture the auto incrementing sequence value as a 
     local variable. */
  SET lv_road_runner_id := last_insert_id();
 
  /* Insert into the coyote table. */
  INSERT INTO coyote
  (coyote_text
  ,road_runner_id)
  VALUES  
  (pv_coyote_text
  ,lv_road_runner_id);
 
  /* Commit the record. */
  COMMIT;
 
  /* Set the control variable to a true value. */
  SET pv_confirm_it := 0;
 
END;
$$
 
DELIMITER ;

You can test the pass-by-reference procedure with the following code:

-- Set a control variable with a null value.
SET @sv_control := null;
 
-- Query the results from a join between the road_runner and coyote tables.
SELECT   *
FROM     road_runner r INNER JOIN coyote c
ON       r.road_runner_id = c.road_runner_id;
 
-- Call the two_table procedure with unique results.
CALL two_table('Road Runner 1','Coyote 1',@sv_control);
 
-- Query the control variable result from the second call to the
-- two_table procedure.
SELECT @sv_control AS "1st Insert";
 
-- Reset the value for a second test.
SET @sv_control := 0;
 
-- Call teh two_table procedure with unique results.  
CALL two_table('Road Runner 2','Coyote 1',@sv_control);  
 
-- Query the results from a join between the road_runner and coyote tables.  
SELECT   *
FROM     road_runner r INNER JOIN coyote c
ON       r.road_runner_id = c.road_runner_id;
 
-- Query the control variable result from the second call to the
-- two_table procedure.
SELECT   @sv_control AS "2nd Insert";

I hope this helps anybody trying to implement a pass-by-reference procedure with a control variable. You can find other examples in Chapter 14 of Oracle Database 11g and MySQL 5.6 Developer Handbook (pp. 446-449 and 450-451).

Written by maclochlainn

February 16th, 2014 at 5:22 pm

Cleanup a MySQL Schema

with 4 comments

My students required way to remove all their tables, views, and constraints from a MySQL database (or the alias schema). Since they’re using referential or foreign key constraints, I also wrote one procedure to drop all foreign key constraints from a database. There’s also another to drop views. The final stored procedure calls the procedure that drops foreign keys, then calls the procedure to drop views before dropping all the tables.

Here’s the dropForeignKeys stored procedure, but if you want to capture ALTER statements that add these back later please check my follow-up Capture MySQL Foreign Keys post.

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-- Provide a log file debugging statement.
SELECT 'DROP PROCEDURE IF EXISTS dropForeignKeys';
 
-- Conditionally drop the procedure.
DROP PROCEDURE IF EXISTS dropForeignKeys;
 
-- Provide a log file debugging statement.
SELECT 'CREATE PROCEDURE dropForeignKeys';
 
-- Change delimiter to create procedure.
DELIMITER $$
 
-- Create procedure.
CREATE PROCEDURE dropForeignKeys
( pv_database          VARCHAR(64)
, pv_referenced_table  VARCHAR(64))
BEGIN
 
  /* Declare local statement variables. */
  DECLARE lv_stmt VARCHAR(1024);
 
  /* Declare local cursor variables. */
  DECLARE lv_table_name       VARCHAR(64);
  DECLARE lv_constraint_name  VARCHAR(64);
 
  /* Declare control variable for handler. */
  DECLARE fetched       INT DEFAULT 0;
 
  /* Declare local cursor. */
  DECLARE foreign_key_cursor CURSOR FOR
    SELECT   rc.table_name
    ,        rc.constraint_name
    FROM     information_schema.referential_constraints rc
    WHERE    constraint_schema = IFNULL(pv_database,database())
    AND      referenced_table_name = pv_referenced_table
    ORDER BY rc.table_name
    ,        rc.constraint_name;
 
  /* Declare a not found record handler to close a cursor loop. */
  DECLARE CONTINUE HANDLER FOR NOT FOUND SET fetched = 1;
 
  /* Open a local cursor. */  
  OPEN foreign_key_cursor;
  cursor_foreign_key: LOOP
 
    FETCH foreign_key_cursor
    INTO  lv_table_name
    ,     lv_constraint_name;
 
    /* Place the catch handler for no more rows found
       immediately after the fetch operation.          */
    IF fetched = 1 THEN LEAVE cursor_foreign_key; END IF;
 
    /* Set a SQL statement by using concatenation. */
    SET @SQL := CONCAT('ALTER TABLE',' ',lv_table_name,' ','DROP FOREIGN KEY',' ',lv_constraint_name);
 
    /* Prepare, run, and deallocate statement. */
    PREPARE lv_stmt FROM @SQL;
    EXECUTE lv_stmt;
    DEALLOCATE PREPARE lv_stmt;
 
  END LOOP cursor_foreign_key;
  CLOSE foreign_key_cursor;  
 
END;
$$
 
-- Reset delimiter to run SQL statements.
DELIMITER ;

Here’s the dropViews stored procedure:

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-- Provide a log file debugging statement.
SELECT 'DROP PROCEDURE IF EXISTS dropViews';
 
-- Conditionally drop the procedure.
DROP PROCEDURE IF EXISTS dropViews;
 
-- Provide a log file debugging statement.
SELECT 'CREATE PROCEDURE dropViews';
 
-- Change delimiter to create procedure.
DELIMITER $$
 
-- Create procedure.
CREATE PROCEDURE dropViews
( pv_database  VARCHAR(64))
BEGIN
 
  /* Declare local statement variables. */
  DECLARE lv_stmt VARCHAR(1024);
 
  /* Declare local cursor variables. */
  DECLARE lv_view_name       VARCHAR(64);
 
  /* Declare control variable for handler. */
  DECLARE fetched       INT DEFAULT 0;
 
  /* Declare local cursor. */
  DECLARE view_cursor CURSOR FOR
    SELECT   v.table_name
    FROM     information_schema.views v
    WHERE    table_schema = IFNULL(pv_database, database())
    ORDER BY v.table_name;
 
  /* Declare a not found record handler to close a cursor loop. */
  DECLARE CONTINUE HANDLER FOR NOT FOUND SET fetched = 1;
 
  /* Open a local cursor. */  
  OPEN view_cursor;
  cursor_view: LOOP
 
    FETCH view_cursor
    INTO  lv_view_name;
 
    /* Place the catch handler for no more rows found
       immediately after the fetch operation.          */
    IF fetched = 1 THEN LEAVE cursor_view; END IF;
 
    /* Set a SQL statement by using concatenation. */
    SET @SQL := CONCAT('DROP VIEW',' ',lv_view_name);
 
    /* Prepare, run, and deallocate statement. */
    PREPARE lv_stmt FROM @SQL;
    EXECUTE lv_stmt;
    DEALLOCATE PREPARE lv_stmt;
 
  END LOOP cursor_view;
  CLOSE view_cursor;  
 
END;
$$
 
-- Reset delimiter to run SQL statements.
DELIMITER ;

Here’s the dropTables stored procedure:

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CREATE PROCEDURE dropTables
( pv_database  VARCHAR(64))
BEGIN
 
  /* Declare local statement variables. */
  DECLARE lv_stmt  VARCHAR(1024);
 
  /* Declare local cursor variables. */
  DECLARE lv_table_name  VARCHAR(64);
 
  /* Declare control variable for handler. */
  DECLARE fetched       INT DEFAULT 0;
 
  /* Declare local cursor. */
  DECLARE table_cursor CURSOR FOR
    SELECT   t.table_name
    FROM     information_schema.tables t
    WHERE    table_schema = IFNULL(pv_database, database())
    ORDER BY t.table_name;
 
  /* Declare a not found record handler to close a cursor loop. */
  DECLARE CONTINUE HANDLER FOR NOT FOUND SET fetched = 1;
 
  /* Drop the views. */
  CALL dropViews(null);
 
  /* Open a local cursor. */  
  OPEN table_cursor;
  cursor_table: LOOP
 
    FETCH table_cursor
    INTO  lv_table_name;
 
    /* Place the catch handler for no more rows found
       immediately after the fetch operation.          */
    IF fetched = 1 THEN LEAVE cursor_table; END IF;
 
    /* Drop the tables. */
    CALL dropForeignKeys(null,lv_table_name);
 
    /* Set a SQL statement by using concatenation. */
    SET @SQL := CONCAT('DROP TABLE',' ',lv_table_name);
 
    /* Prepare, run, and deallocate statement. */
    PREPARE lv_stmt FROM @SQL;
    EXECUTE lv_stmt;
    DEALLOCATE PREPARE lv_stmt;
 
  END LOOP cursor_table;
  CLOSE table_cursor;  
 
END;
$$
 
-- Reset delimiter to run SQL statements.
DELIMITER ;

You put these in a rerunnable script, run it, and then call the dropTables stored procedure. You can pass a database (or schema) name or a null value. When you pass a null value, it uses the current database, like:

CALL dropTables(null);

As always, I hope this helps others.

Written by maclochlainn

February 7th, 2014 at 1:38 am

Mac Mini to the rescue

with 7 comments

In teaching, I had a problem because my students have different base operating systems, like Windows 7, Windows 8, Linux, and Mac OS X. I needed a teaching and lecture platform that would let me teach it all (not to mention support their environments). That meant it had to virtualize any of the following with a portable device:MacMiniConsole

  • Windows 7 or 8 hosting natively an Oracle Database 11g XE, 11g, or 12c and MySQL Database 5.6
  • Windows 7 or 8 hosting a Fedora or Oracle Unbreakable Linux VM (3 or 4 GB) with Oracle Database 11g XE, 11g, or 12c and MySQL Database 5.6
  • Mac OS X hosting a Fedora or Oracle Unbreakable Linux VM (3 or 4 GB) with Oracle Database 11g XE, 11g, or 12c and MySQL Database 5.6
  • Ubuntu hosting a Fedora or Oracle Unbreakable Linux VM (3 or 4 GB) with Oracle Database 11g XE, 11g, or 12c and MySQL Database 5.6

I never considered a manufacturer other than Apple for a laptop since they adopted the Intel chip. Too many of the others sell non-hyperthreaded laptop machines that they market as i5 or i7 64-bit OS machines when they’re not. Some of those vendors disable the hyperthreading facility while others provide motherboards that can’t support hyperthreading. The ones I dislike the most provide a BIOS setting that gives the impression you can enable hyperthreading when you can’t. All Apple devices, MacBook, MacBook Pro, Mac Mini, and Mac Pro do fully support a 64-bit OS and their virtualization.

A MacBook Pro came to mind but the disk space requirements were 1 TB, and that’s too pricey. I went with the Mac Mini because with 16 GB of memory and a 1 TB drive it was only $1,200. Add a wireless keyboard and mighty mouse, and an HDMI and mini-DVI connections, and I had my solution. Naturally, my desktop is a one generation old Mac Pro with 64 GB of memory and 12 TB of disk space, which supports all the virtual machines used for testing. Note to Apple marketing staff: The prior version of the Mac Pro let you pay reasonable (3rd party) prices for the additional memory and disk drives.

The Mac Mini means I can travel anywhere and plug into the console and demo tools and techniques from a myriad set of platforms without the hassle of moving on and off to frequently VM images. It’s a great solution with only one downside, HDMI to DVI sometimes creates purple toned screens. It’s unfortunate because some venues have monitors that don’t support HDMI).

Written by maclochlainn

February 6th, 2014 at 12:17 pm

Oracle 12c PL/SQL Published

with 2 comments

Oracle Database 12c PL./SQL ProgrammingAfter writing nine books, it’s always great when the author copies arrive. That’s when I know the process is complete. Friday, my twelve copies of the Oracle Database 12c PL/SQL Programming book arrived in two boxes of six each. The book is also available online at Amazon.com.

The book qualifies all the Oracle 12c new SQL and PL/SQL features. I added review sections and mastery questions to each chapter, and expanded examples and techniques. To conserve space and avoid reprinting duplicate code blocks, I adopted line numbers for the code segments so I could provide the technique variations by line numbers for alternate solutions.

You have complete examples on how to white list functions, procedures, packages, and object types with the new ACCESSIBLE BY clause. Likewise, you’ll learn how to use your PL/SQL variables inside embedded queries.

The improved collection coverage shows you how to write PL/SQL functions that let you use unnested UPDATE statements to add, change, and remove elements from Attribute Data Types (ADTs), and the expanded SQL Primer shows you how to update nested User-Defined Types (UDTs) without having to write PL/SQL. The book also shows you how to export object tables or columns into relational tables for ETL processes.

Oracle12cBooksArriveThe Oracle Database Primer grew to include more database administration, multiversion concurrency control, SQL tuning, and SQL tracing. The SQL Primer now contains expanded coverage on data types, Data Definition Language (DDL), Data Manipulation Language (DML), Transaction Control Language (TCL), SQL queries, joins, and unnesting queries. The SQL Built-in Functions appendix was expanded to enable me to remove side discussions about SQL elements from the PL/SQL chapters. John Harper wrote some wonderful examples of DBMS_COMPARISON, DBMS_CRYPTO, and DBMS_FGA to supplement the PL/SQL Built-in Packages and Types appendix. The Regular Expression Primer was rewritten to make it easier to read and use.

I’ve created an Errata for the Oracle Database 12c PL/SQL Programming. If you buy a copy and find an error, please post a comment in the errata.

Written by maclochlainn

February 1st, 2014 at 9:31 pm

Open a port on Fedora

with one comment

Since MySQL Workbench 6.0 isn’t available for Fedora, Version 20, I’m having my students install it on their local Windows and Mac OS X operating systems. You can configure the /etc/sysconfig/iptables file to enable port 3306 after installing MySQL on Fedora.

You can open a port by adding the following line to the /etc/sysconfig/iptables file (Fedora’s instructions on editing iptables). The file won’t exist initially, but you can create it by running the following command as the root superuser or sudoer:

shell> service iptables save

You you can run the following commands as the root superuser, which saves the line in the iptables file:

shell> iptables -A INPUT -m conntrack --ctstate NEW -m tcp -p tcp --dport 3306 -j ACCEPT
shell> iptables-save

After making the change to the /etc/iptables file you can change the firewall by running the following command as the root superuser:

shell> service iptables restart

Just make sure you don’t inadvertently start both iptables and ip6tables as services. You can check that only one is running by using the following commands:

shell> service iptables status
shell> service ip6tables status

MySQL Workbench Configuration

MySQL Workbench Home Page

  1. The first thing you need to do is click on the + symbol in the circle to the right of the MySQL Connections text label. It launches the Setup New Connection dialog.

Setup New Connection

  1. The second thing you need to do is enter a Connection Name, Hostname, Port, and Username. Then, click the Test Connection button.

Connect to MySQL Server

  1. The Test Connection button launches the Connect to MySQL Server dialog. Enter the password for the student user (or whatever user you’re interested in), and then click the OK button.

Connection Parameter Acknowledgment

  1. When the credentials in the Connect to MySQL Server dialog work, you see the following confirmation dialog message. Click the OK button to continue and you’ll see a new VMWare Fedora Instance connection icon.

MySQL Workbench Home Page

  1. Click the VMWare Fedora Instance connection to start a new connection.

Connect to MySQL Server

  1. The VMWare Fedora Instance button launches the Connect to MySQL Server dialog. Like you did when configuring the connection, enter the password for the student user (or whatever user you’re interested in), and then click the OK button. It launches an interactive panel that lets you run, edit, or save the SQL script file.

MySQL Workbench

  1. Type the following two lines in the Query1 panel (at least if you have a studentdb database:

    USE studentdb;
    SELECT DATABASE();

Written by maclochlainn

January 18th, 2014 at 11:51 pm