The following statement uses the COUNT(*) function with a WHERE clause to find the number of tracks whose album id is 10: SELECT COUNT(*) To get the number of rows from the tracks table, you use the COUNT(*) function as follows: SELECT count(*)įROM tracks Code language: SQL (Structured Query Language) ( sql )ģ503 Code language: plaintext ( plaintext ) 2) SQLite COUNT(*) with WHERE clause example We will take the table tracks in the sample database to demonstrate the functionality of the COUNT(*) function. Sixth, use the COUNT(DISTINCT expression) to get the number of unique and non-null values in column c: SELECT COUNT( DISTINCT c) FROM t1 Code language: SQL (Structured Query Language) ( sql ) SQLite COUNT(*) examples It counts the duplicate rows as separate rows. In this example, the COUNT(c) returns the number of non-null values. Third, query data from the t1 table: SELECT * FROM t1 Code language: SQL (Structured Query Language) ( sql )įourth, use the COUNT(*) function to return the number of rows in the t1 table: SELECT COUNT(*) FROM t1 Code language: SQL (Structured Query Language) ( sql )Īs you can see clearly from the output, the result set includes NULL and duplicate rows.įifth, use the COUNT(expression) to get the number of non-null values in the column c: SELECT COUNT(c) FROM t1 Code language: SQL (Structured Query Language) ( sql ) VALUES( 1),( 2),( 3),( null),( 3) Code language: SQL (Structured Query Language) ( sql ) Second, insert five rows into the t1 table: INSERT INTO t1(c) SQLite COUNT() function illustrationįirst, create a table called t1 that has one column: CREATE TABLE t1(c INTEGER) Code language: SQL (Structured Query Language) ( sql ) The COUNT(*) function returns the number of rows in a table, including the rows including NULL and duplicates. SQLite provides another syntax of the COUNT() function: COUNT(*) Code language: SQL (Structured Query Language) ( sql ) The expression can be a column or an expression that involves columns to which the function COUNT() is applied. DISTINCT: if you explicitly use the DISTINCT option, the COUNT function counts only unique and non-null values.The COUNT() function uses the ALL option by default if you skip it. ALL: when you specify all, the COUNT() function counts all non-null values include duplicates.The following describes the meanings of ALL and DISTINCT options: The COUNT function behaves according to the arguments that you pass into it and the option ALL or DISTINCT that you specify. ![]() The following illustrates the basic syntax of the COUNT function: COUNT( expression) Code language: SQL (Structured Query Language) ( sql ) Arguments The function COUNT() is an aggregate function that returns the number of items in a group.įor example, you can use the COUNT() function to get the number of tracks from the tracks table, the number of artists from the artists table, and so on. I therefore suspect that they have no intention to add more fuel to the fire, when they will eventually try to fix the root cause.Summary: in this tutorial, you will learn how to use SQLite COUNT function to get the number of items in a group. One might ask why not deviate further from the standard and allow a 4-row result? It's just a guess, but I suspect that the intention is to fix the first deviation eventually (probably via a setting similar to MySQL). Therefore, one row is randomly picked, say john, 3 ![]() Since an aggregate function (in this case COUNT) is supposed to aggregate per group, we should get 1 row in the result (we only have 1 group, the group for the empty set). Null is not taken into consideration by count, so we end up with: jack, 3 This means that your aggregate function applies to all rows in the result set, i.e. You can think of your query as if it looks like: SELECT first_name, COUNT(first_name) SQLite refers to first_name outside of the aggregate as a "bare" column, see section 2.5. SQLite does not adhere to the standard in this regard.
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