SELECTDISTINCTcolumn1, column2 ...FROMtable; Here, column1, column2, ...are the table columns tableis table name from where we retrieve the distinct columns Example: SQL SELECT DISTINCT -- select the unique countries from the customers tableSELECTDISTINCTcountryFROMCustomers; Run Code Here, the...
SELECT DISTINCT accountid FROM table; COUNT DISTINCT子句 命令简介 COUNT DISTINCT支持计算去重之后的某一个column的个数,对于该列中出现多次的值只会被计算一次,和COUNT的计算类似,如果该列包含NULL值,它将不会计算在内。 语法说明 精确计算的语法示例如下: SELECT c1, COUNT(DISTINCT c2) FROM table GROUP BY...
SELECT DISTINCT 关键字 SQL的SELECT DISTINCT语句用于选择表中的不同(唯一)值。...SELECT DISTINCT的基本语法如下: SELECT DISTINCT column1, column2, ...计算不同国家的数量: SELECT COUNT(DISTINCT Country) FROM Customers; 此语句使用COUNT函数来计算不同国家的数量。...请注意,某些数据库系统可能不支持COUNT...
You can use the count() function in a select statement with distinct on multiple columns to count the distinct rows. Here is an example: SELECTCOUNT(*)-- Count the number of rows in the result setFROM(SELECTDISTINCTagent_code,ord_amount,cust_code-- Select distinct combinations of 'agent_c...
在SQL查询中,COUNT 和DISTINCT 是两个常用的聚合函数,它们可以组合使用来获取唯一值的数量。COUNT(DISTINCT column_name) 用于返回指定列中不同值的数量。 基础概念 COUNT: 是一个聚合函数,用于计算行数。它可以计算表中的总行数或特定条件下的行数。 DISTINCT: 关键字用于返回唯一不同的值。 相关优势 精确计数:...
DISTINCT 的两个问题,用 ROW_NUMBER() OVER 可解。比如,如果我们要按 key1 和 key2 两列为 key 去重,就会写出这样的代码: WITH temp_table AS ( SELECT key1, key2, [columns]..., ROW_NUMBER() OVER ( PARTITION BY key1, key2 ORDER BY column ASC ...
SELECT DISTINCT accountid FROM table; COUNT DISTINCT子句 命令简介 COUNT DISTINCT支持计算去重之后的某一个column的个数,对于该列中出现多次的值只会被计算一次,和COUNT的计算类似,如果该列包含NULL值,它将不会计算在内。 语法说明 精确计算的语法示例如下: SELECT c1, COUNT(DISTINCT c2) FROM table GROUP BY...
SELECTDISTINCTcolumn-name FROMtable-name DISTINCT syntax with COUNT or other aggregates. SELECTCOUNT(DISTINCTcolumn-name) FROMtable-name More Examples # SELECT DISTINCT Problem: List all unique supplier countries in alphabetical order. SELECTDISTINCTCountryFROMSupplierORDERBYCOUNTRY ...
Select COUNT(DISTINCT name_of_column1), COUNT(DISTINCT name_of_column2), …, COUNT(DISTINCT name_of_columnN) from name_of_table; Below is the description syntax of SQL select distinct with count statement is as follows. Count –We are using count with SQL select distinct for retrieving a...
Cannot update identity column 'ItemID'. Cannot update the view or function "CTE" because it contains aggregates or a DISTINCT clause. Cannot use an aggregate or a subquery in an expression used for the group by list of a GROUP BY clause. Cannot use the ROLLBACK statement within an INSERT...