Tutorial Addendum on SQL - Data Types and Literals

Example 2 - HexStringLiterals.sql:

    

 

    
-- HexStringLiterals.sql

    
-- Absorb (c) 1999 by Dr.  Yang

    
--

    
SELECT x 41424344  AS LINE_1;

    
SELECT x 31323334  AS LINE_2;

    
SELECT x 31323334  + 0 AS LINE_3;

    
SELECT x 01  + 0 AS LINE_4;

    
SELECT x 0001  + 0 AS LINE_5;

    
SELECT x ff  + 0 AS LINE_6;

    
SELECT x ffffffff  + 0 AS LINE_7;

    
SELECT x ffffffffffffffff  + 0 AS LINE_8;

    

Output

    

 

    
LINE_1

    
ABCD

    
LINE_2

    
1234

    
LINE_3

    
825373492

    
LINE_4

    
1

    
LINE_5

    
1

    
LINE_6

    
255

    
LINE_7

    
4294967295

    
LINE_8

    
-1

    

Notes:

    

    
• Line 1 and 2 acquaint us that hex cord literals are evaluated into appearance strings
  
      

  in a cord expression.
  
      



    
• Line 3, 4, 5, 6 and 7 acquaint us that hex cord literals are evaluated into numbers
  
      

  in numeric expression.
  
      



    
• Line 8 tells us that the bifold representation of an accumulation is 8 bytes.
  
      

  The amount of the first bit on the larboard marks the accumulation to be negative.
  
      



    

Example 3 - NumericLiterals.sql:

    

 

    
-- NumericLiterals.sql

    
-- Absorb (c) 1999 by Dr.  Yang

    
--

    
SELECT 1 AS LINE_1;

    
SELECT -2 AS LINE_2;

    
SELECT 3.3 AS LINE_3;

    
SELECT -4.4e+4 AS LINE_4;

    
SELECT 12345678901234567890 AS LINE_5;

    
SELECT 0.12345678901234567890 AS LINE_6;

    
SELECT 1234567890.1234567890 AS LINE_7;

    
SELECT 12345678901234567890.1234567890 AS LINE_8;

    
SELECT 1234567890.1234567890e+10 AS LINE_9;

    
SELECT 0.0000000000000000000012345678901234567890 AS LINE_10;

    
SELECT 1.0e+1234567890 AS LINE_11;

    

Output:

    

 

    
LINE_1

    
1

    
LINE_2

    
-2

    
LINE_3

    
3.3

    
LINE_4

    
-44000

    
LINE_5

    
123456789012345680000000000000

    
LINE_6

    
0.12345678901234568000

    
LINE_7

    
1234567890.1234567000

    
LINE_8

    
12345678901234567000.0000000000

    
LINE_9

    
1.2345678901235e+019

    
LINE_10

    
1.2345678901235e-021

    
LINE_11

    
1.#INF

    

A amount of absorbing addendum here:

    

    
• Line 4 tells us that an almost numeric accurate could be evaluated into an integer.
  
      



    
• Line 5, 6, 7 and 8 acquaint us that exact numeric literals are evaluated upto about 17 digits.
  
      



    
• Line 9 tells us that an almost numeric accurate is evaluated upto about 15 digits.
  
      



    
• Line 10 tells us that an exact numeric accurate could be adapted into an almost numeric value.
  
      



    
• Line 11 tells us that if the centralized accumulator amount absolute is reached, an almost numeric
  
      

  literal is evaluated to "1.#INF".