COUNT (Lakehouse v1)

The COUNT() function returns the number of records returned by a SELECT query.

Analyze Syntax

func.count(<column>)

Analyze Examples

func.count(table.grade).alias('count_valid_grades')

| count_valid_grades |
|--------------------|
|          4         |

SQL Syntax

COUNT(<expr>)

Arguments

Arguments	Description
`<expr>`	Any expression. This may be a column name, the result of another function, or a math operation. `*` is also allowed, to indicate pure row counting.

Return Type

An integer.

SQL Examples

Create a Table and Insert Sample Data

CREATE TABLE students (
  id INT,
  name VARCHAR,
  age INT,
  grade FLOAT NULL
);

INSERT INTO students (id, name, age, grade)
VALUES (1, 'John', 21, 85),
       (2, 'Emma', 22, NULL),
       (3, 'Alice', 23, 90),
       (4, 'Michael', 21, 88),
       (5, 'Sophie', 22, 92);

Query Demo: Count Students with Valid Grades

SELECT COUNT(grade) AS count_valid_grades
FROM students;

Result

| count_valid_grades |
|--------------------|
|          4         |