1.26. SQLite Distinct keyword

发布时间 : 2025-10-25 12:31:17 UTC      

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SQLite’s DISTINCT Keywords vs. SELECT Statement to eliminate all duplicate records and get only one record.

It is possible to have multiple duplicate records in a table. When extracting such a record, the DISTINCT keyword is particularly meaningful, which only gets the only record, not the duplicate record.

1.26.1. Grammar

Used to eliminate duplicate records DISTINCT The basic syntax for keywords is as follows:

SELECT DISTINCT column1, column2,.....columnN
FROM table_name
WHERE [condition]

1.26.2. Example

Hypothetical COMPANY The table has the following records:

ID          NAME        AGE         ADDRESS     SALARY
----------  ----------  ----------  ----------  ----------
1           Paul        32          California  20000.0
2           Allen       25          Texas       15000.0
3           Teddy       23          Norway      20000.0
4           Mark        25          Rich-Mond   65000.0
5           David       27          Texas       85000.0
6           Kim         22          South-Hall  45000.0
7           James       24          Houston     10000.0
8           Paul        24          Houston     20000.0
9           James       44          Norway      5000.0
10          James       45          Texas       5000.0

First, let’s take a look at the following SELECT Query, which returns duplicate payroll records:

sqlite> SELECT name FROM COMPANY;

This will produce the following results:

NAME
----------
Paul
Allen
Teddy
Mark
David
Kim
James
Paul
James
James

Now, let’s look at the above SELECT Used in query DISTINCT Keywords:

sqlite> SELECT DISTINCT name FROM COMPANY;

This will produce the following results without any duplicate entries:

NAME
----------
Paul
Allen
Teddy
Mark
David
Kim
James
Principles, Technologies, and Methods of Geographic Information Systems  102

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