How do I use distinct on all columns in SQL?

SELECT DISTINCT FIELD1, FIELD2, FIELD3 FROM TABLE1 works if the values of all three columns are unique in the table. If, for example, you have multiple identical values for first name, but the last name and other information in the selected columns is different, the record will be included in the result set. 25 мая 2011 г. Select with distinct on all columns of the first query Select with distinct on multiple columns and order by clause Count () function and select with distinct on multiple columns

Can you select distinct on multiple columns?

Answer. Yes, the DISTINCT clause can be applied to any valid SELECT query. It is important to note that DISTINCT will filter out all rows that are not unique in terms of all selected columns. Feel free to test this out in the editor to see what happens!

Can distinct be used on multiple columns MySQL?

MySQL DISTINCT with multiple columns When you specify multiple columns in the DISTINCT clause, the DISTINCT clause will use the combination of values in these columns to determine the uniqueness of the row in the result set.

What will happen if you apply distinct on whole table?

Adding the DISTINCT keyword to a SELECT query causes it to return only unique values for the specified column list so that duplicate rows are removed from the result set. Since DISTINCT operates on all of the fields in SELECT's column list, it can't be applied to an individual field that are part of a larger group.

How can I count distinct values of all columns in SQL?

To count the number of different values that are stored in a given column, you simply need to designate the column you pass in to the COUNT function as DISTINCT . When given a column, COUNT returns the number of values in that column. Combining this with DISTINCT returns only the number of unique (and non-NULL) values.

What is the use of distinct in SQL?

DISTINCT will eliminate those rows where all the selected fields are identical. Contents: Sample Select statement. Select with distinct on two columns. Select with distinct on three columns. Select with distinct on all columns of the first query. Select with distinct on multiple columns and order by clause.

How to select with distinct on two columns?

Example: SELECT with DISTINCT on two columns. To get the identical rows (based on two columns agent_code and ord_amount) once from the orders table, the following SQL statement can be used : SQL Code: SELECT DISTINCT agent_code,ord_amount FROM orders WHERE agent_code='A002'; Output:

How to use ORDER BY clause in select statement with distinct?

You can use an order by clause in the select statement with distinct on multiple columns. Here is an example: You can use the count () function in a select statement with distinct on multiple columns to count the distinct rows.

How to count the distinct rows on multiple columns in MySQL?

Count () function and select with distinct on multiple columns. You can use count() function in a select statement with distinct on multiple columns to count the distinct rows. Here is an example :