Print different star patterns in SQL

Creating star patterns directly in SQL is not conventional, as SQL is primarily designed for data querying and manipulation. However, it's possible to produce simple star patterns using SQL's string functions and recursive common table expressions (CTEs) or other techniques.

Below are SQL examples for a few star patterns, using T-SQL syntax (as used in Microsoft SQL Server). The approach would be similar in other database systems, with some adjustments based on syntax differences:

Right-Angled Triangle:

WITH CTE AS (
    SELECT 1 AS level
    UNION ALL
    SELECT level + 1
    FROM CTE
    WHERE level < 5  -- Change 5 to adjust the triangle's height
)
SELECT REPLICATE('*', level) AS Pattern
FROM CTE;

Inverted Right-Angled Triangle:

WITH CTE AS (
    SELECT 5 AS level  -- Change 5 to adjust the triangle's height
    UNION ALL
    SELECT level - 1
    FROM CTE
    WHERE level > 1
)
SELECT REPLICATE('*', level) AS Pattern
FROM CTE;

Pyramid Pattern:

WITH CTE AS (
    SELECT 1 AS level
    UNION ALL
    SELECT level + 1
    FROM CTE
    WHERE level < 5  -- Change 5 to adjust the pyramid's height
)
SELECT 
    REPLICATE(' ', 5 - level) + -- Adjust 5 based on pyramid's height
    REPLICATE('*', 2 * level - 1) AS Pattern
FROM CTE;

These examples utilize recursive CTEs to generate a series of numbers, and then the REPLICATE function is used to produce the necessary number of stars (or spaces) for each row of the pattern.

If you're working in a different database system, the recursive method might be similar, but the string manipulation functions (e.g., REPLICATE) could have different names or slight variations in behavior. Always remember to adjust for recursion limits in systems like SQL Server, or the query may enter an infinite loop.

SQL query to print a simple star pattern:
- Use a SQL query to print a simple star pattern.
```
SELECT '*****' AS star_pattern FROM dual;
```
Star pattern printing in SQL stored procedure:
- Create a stored procedure in SQL for printing a star pattern.
```
CREATE OR REPLACE PROCEDURE print_star_pattern AS
BEGIN
    DBMS_OUTPUT.PUT_LINE('*****');
END;
/
```

Generating star patterns using SQL:

Use a SQL query to generate various star patterns.

-- Example of a right-angled triangle star pattern
SELECT '*
       **
       ***
       ****
       *****' AS star_pattern
FROM dual;

Print right-angled triangle star pattern in SQL:
- Use a SQL query to print a right-angled triangle star pattern.
```
SELECT LEVEL
FROM dual
CONNECT BY LEVEL <= 5;
```

SQL query for printing hollow square star pattern:

Use a SQL query to print a hollow square star pattern.

SELECT CASE
           WHEN rownum = 1 OR rownum = 5 THEN '*****'
           ELSE '*' || RPAD(' ', 3, ' ') || '*'
       END AS star_pattern
FROM dual
CONNECT BY LEVEL <= 5;

Star patterns with nested loops in SQL:
- Utilize nested loops in a SQL query for more complex star patterns.
```
SELECT LEVEL, LPAD('*', LEVEL, '*') AS star_pattern
FROM dual
CONNECT BY LEVEL <= 5;
```
Print inverted pyramid star pattern in SQL:
- Use a SQL query to print an inverted pyramid star pattern.
```
SELECT RPAD('*', 6 - LEVEL, '*') AS star_pattern
FROM dual
CONNECT BY LEVEL <= 5;
```

Creating diamond star pattern in SQL:

Use a SQL query to print a diamond star pattern.

SELECT RPAD(' ', 5 - LEVEL, ' ') || LPAD('*', 2 * LEVEL - 1, '*') AS star_pattern
FROM dual
CONNECT BY LEVEL <= 5
UNION
SELECT RPAD(' ', LEVEL - 1, ' ') || LPAD('*', 11 - 2 * LEVEL, '*') AS star_pattern
FROM dual
CONNECT BY LEVEL <= 4;

SQL stored procedure for printing pyramid star pattern:

Create a stored procedure in SQL for printing a pyramid star pattern.

CREATE OR REPLACE PROCEDURE print_pyramid_star_pattern AS
BEGIN
    FOR i IN 1..5 LOOP
        DBMS_OUTPUT.PUT_LINE(RPAD(' ', 5 - i, ' ') || LPAD('*', 2 * i - 1, '*'));
    END LOOP;
END;
/

SQL query to print mirrored right-angled star pattern:
- Use a SQL query to print a mirrored right-angled star pattern.
```
SELECT RPAD('*', LEVEL, '*') AS star_pattern
FROM dual
CONNECT BY LEVEL <= 5;
```