TRIM

-- Eliminar espacios de ambos lados
TRIM(cadena)
 
-- Sintaxis completa
TRIM([{BOTH | LEADING | TRAILING} [caracter] FROM] cadena)

SELECT TRIM('   Hola mundo   ') AS resultado;

SELECT
    CONCAT('[', '   espacios   ', ']') AS original,
    CONCAT('[', TRIM('   espacios   '), ']') AS trimmed;

SELECT
    CONCAT('[', TRIM(LEADING FROM '   Hola   '), ']') AS leading,
    CONCAT('[', TRIM(TRAILING FROM '   Hola   '), ']') AS trailing,
    CONCAT('[', TRIM(BOTH FROM '   Hola   '), ']') AS both_sides;

SELECT TRIM(BOTH '*' FROM '***Hola***') AS resultado;

SELECT TRIM(LEADING '0' FROM '00042') AS resultado;

SELECT TRIM(TRAILING '.' FROM 'Hola...') AS resultado;

-- Simular datos sucios con espacios
SELECT
    nombre,
    CONCAT('[', TRIM(nombre), ']') AS limpio
FROM productos
LIMIT 3;

-- Buscar ignorando espacios extra
SELECT nombre, precio
FROM productos
WHERE TRIM(nombre) = 'iPhone 15 Pro';

-- Limpiar espacios de todos los nombres
-- UPDATE productos SET nombre = TRIM(nombre);
-- UPDATE clientes SET email = TRIM(email);