This SQL tutorial explains how to use the SQL DISTINCT clause with syntax and examples. The SQL DISTINCT clause is used to remove duplicates from the result set of a SELECT statement.
CASE子句用于查找支付状态 现在我需要在SQL中对从CASE-statement计算出来的结果进行过滤,例如,如果在过滤器中选择了"Paid“,那么我们只需要看到那些支付状态为"Paid”的记录。我知道我们不能在WHERE子句中使用别名。 在我的例子中,我在WHERE子句中添加了一个名为"pm_clause“的别名,但在下面的SQL中添加了一个...
Statement names are not case sensitive. preparable_stmt is either a string literal or a user variable that contains the text of the statement. The text must represent a single SQL statement, not multiple statements. Within the statement, ‘?’ characters can be used as parameter markers to ind...
If you want to select a list of all unique colors from all rows in the table, you can accomplish it by using the following SQL statement: SELECT DISTINCT Color FROM Cars; The DISTINCT keyword goes right away after the SELECT keyword, and in turn is followed by the column(s) we are se...
The above result shows the sameagent_code,ord_amountandcust_codeappears more than once in theorderstable. Example: SELECT with DISTINCT on two columns The SQL statement below retrieves identical rows based on the 'agent_code' and 'ord_amount' columns from the orders table : ...
We use the DISTINCT Statement along with theSELECT statement. The syntax for theDISTINCTclause is as follows: SELECTDISTINCTexpressionsFROMtable_name;Code language:SQL (Structured Query Language)(sql) Examples of the DISTINCT Clause Let us consider the following ConferenceGuests table. ...
Mysql中的条件语句在我们对数据进行转换的时候比较有用,这样就不需要创建中转表。...= "" IF ELSE 流程控制语句在mysql存储过程中的用法: IF search_condition THEN statement_list [ELSEIF search_condition...[ELSE st...
The DistinctCount function returns the distinct number of items in a set; in this example, the optional second parameter is used to exclude items that don't have a value for a given tuple. In this case there are four distinct items in the set in the first parameter, but the function re...
-- The Distinct keyword must only be used before the first column in the query SELECT StudentId,Distinct(Name) FROM dbo.Student Common use cases Let us now discuss the common use cases of SQL SELECT Distinct statement. Analyzing and Improving data accuracy based on distinct values Suppose ...
如何在distinct子句中执行case语句？distinct不是函数。它应用于所有选定的列，并生成所有选定列的唯一组合...