SHIFTLEFT

shiftleft(value, n)

Function

Performs a left bit-shift operation on an integer value. Shifting left by n bits is equivalent to multiplying by 2n. Supports int and bigint types.

Parameters

• value: int or bigint type, the value to shift
• n: int type, the number of bit positions to shift; must be greater than or equal to 0

Return Value

• The same type as value (int or bigint)
• Returns the result after the left shift
• Returns NULL if value or n is NULL

Examples

SELECT shiftleft(1, 2); -- Result: 4

SELECT shiftleft(8, 2); -- Result: 32

SELECT shiftleft(0, 2); -- Result: 0

SELECT shiftleft(1L, 2); -- Result: 4

SELECT shiftleft(8L, 2); -- Result: 32

SELECT shiftleft(NULL, 2); -- Result: NULL

SELECT shiftleft(1, NULL); -- Result: NULL

SELECT shiftleft(-4, 2); -- Result: -16

SELECT shiftleft(1, 10); -- 210 = 1024 -- Result: 1024

Notes

• Shifting left by n bits is equivalent to multiplying by 2n
• For positive numbers: shiftleft(x, n) = x * 2n
• For negative numbers, the left shift preserves the sign bit
• Shift operations can cause overflow:
  • int range: -2,147,483,648 to 2,147,483,647
  • bigint range: -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
• If the result exceeds the type range, overflow occurs (result is undefined)
• Bit-shift operations are faster than multiplication
• Common use cases:
  • Fast computation of powers of 2
  • Bit flag and bit mask operations
  • Data encoding and decoding
• Related functions:
  • shiftright — arithmetic right shift (preserves sign bit)
  • shiftrightunsigned — logical right shift (does not preserve sign bit)