PL/SQL commands to view the table details

13 November 2024

In Oracle PL/SQL, you can use the following commands to view table details:

  1. DESCRIBE or DESC

    DESC table_name;
    

    Displays columns, data types, and constraints.

  2. USER_TAB_COLUMNS

    SELECT COLUMN_NAME, DATA_TYPE, DATA_LENGTH
    FROM USER_TAB_COLUMNS
    WHERE TABLE_NAME = 'TABLE_NAME';
    

    Shows details about columns for tables owned by the user.

  3. ALL_TAB_COLUMNS

    SELECT COLUMN_NAME, DATA_TYPE, DATA_LENGTH
    FROM ALL_TAB_COLUMNS
    WHERE TABLE_NAME = 'TABLE_NAME';
    

    Provides column information for tables accessible to the user.

  4. DBMS_METADATA.GET_DDL

    SELECT DBMS_METADATA.GET_DDL('TABLE', 'TABLE_NAME') FROM DUAL;
    

    Displays the CREATE TABLE statement for table structure details.

To view constraints on the table, you can check here.

Use Flashback Query

11 November 2024

If your Oracle database has Flashback enabled, you can query past versions of data within a specified retention period. Here’s how to use Flashback to retrieve a prior state of data:

SELECT * 
FROM your_table AS OF TIMESTAMP (SYSTIMESTAMP - INTERVAL '5' MINUTE) 
WHERE your_condition;

Replace SYSTIMESTAMP - INTERVAL '5' MINUTE with the timestamp or interval that reflects when the data was last known to be in its old state.

Note: Flashback must be enabled, and it’s only available within the Flashback retention window, which depends on your database configuration.

References

Killians Bytes

How to break columns in Bootstrap

3 November 2024

Breaking columns to a new line in flexbox requires a small hack: add an element with width: 100% wherever you want to wrap your columns to a new line.

<div class="container text-center">
  <div class="row">
    <div class="col-6 col-sm-3">.col-6 .col-sm-3</div>
    <div class="col-6 col-sm-3">.col-6 .col-sm-3</div>

    <!-- Force next columns to break to new line -->
    <div class="w-100"></div>

    <div class="col-6 col-sm-3">.col-6 .col-sm-3</div>
    <div class="col-6 col-sm-3">.col-6 .col-sm-3</div>
  </div>
</div>

You can also apply this break at specific breakpoints with our responsive display utilities.

<div class="container text-center">
  <div class="row">
    <div class="col-6 col-sm-4">.col-6 .col-sm-4</div>
    <div class="col-6 col-sm-4">.col-6 .col-sm-4</div>

    <!-- Force next columns to break to new line at md breakpoint and up -->
    <div class="w-100 d-none d-md-block"></div>

    <div class="col-6 col-sm-4">.col-6 .col-sm-4</div>
    <div class="col-6 col-sm-4">.col-6 .col-sm-4</div>
  </div>
</div>
References

Bootstrap Doc

സ്നേഹം?

2 November 2024

എന്താണ് സ്നേഹം?

നിനക്ക് വേദനിക്കുമ്പോളെല്ലാം
എനിക്കും വേദനിക്കുന്നത്.

Salmaniya water garden park

1 November 2024

Salmaniya, Bahrain

Salmaniya, Bahrain

To generate random value in PL/SQL

30 October 2024

To update a column with a random value in PL/SQL, you can use the DBMS_RANDOM package, which provides functions for generating random numbers or strings.

To update random number

BEGIN
    UPDATE employees
    SET salary = ROUND(DBMS_RANDOM.VALUE(100, 500));
    COMMIT;
END;
  • DBMS_RANDOM.VALUE(100, 500) generates a random decimal number between 100 and 500.
  • ROUND is used to convert the decimal value to an integer.

To update random string

BEGIN
   UPDATE employees
    SET password = DBMS_RANDOM.STRING('x', 8);  -- 'x' specifies alphanumeric characters
    COMMIT;
END;
  • DBMS_RANDOM.STRING('x', 8) generates an 8-character alphanumeric string.
  • ‘x’ specifies alphanumeric characters (letters and numbers). Other options include ‘a’ for alphabets and ‘u’ for uppercase only.

വഴിയമ്പലങ്ങൾ

25 October 2024

ഹൃദയത്തിൽ വഴിയമ്പലങ്ങൾ കണക്കെ
ഇടങ്ങൾ ഉണ്ടായിരിക്കണം.
കോരിച്ചൊരിയുന്ന മഴയത്ത് ഓടിക്കയറാനും
ഒരു പുലരിയിൽ വിട പറയാതെ
യാത്ര തുടങ്ങാനും സാധിക്കുന്ന
മനോഹരയിടങ്ങൾ.

Migrating my posts from social media

23 October 2024

I want to migrate my favorite memories from various social media platforms to this blog. I’m not sure it will work, but I still want to give it a try because I love the idea of having all my favorite things in one place.

Hopefully, I can do it gradually over time.

Update on 27 Oct: I already started migrating my posts from various social medias. Its a tedious task, but I am loving it.

My plants and my poems

23 October 2024

My plants and my poems.