ORDER BY transaction_id) AS Duplicate_row FROM Transaction__Table WITH CTE AS (SELECT *, ROW_NUMBER() OVER(PARTITION BY transaction_id ORDER BY transaction_id) AS Duplicate_rows FROM Transaction__Table) DELETE FROM CTE WHERE Duplicate_rows >1; 现在重复值消失了。 确保数据类型准确:另一个重要...
SELECTDISTINCT*INTOduplicate_tableFROMoriginal_tableGROUPBYkey_valueHAVINGCOUNT(key_value) >1DELETEoriginal_tableWHEREkey_valueIN(SELECTkey_valueFROMduplicate_table)INSERToriginal_tableSELECT*FROMduplicate_tableDROPTABLEduplicate_table 此脚本按给定顺序执行以下操作: ...
Selection(选择): A select operation selects a subset of rows (records) in a table (relation) that satisfy a selection condition. The ability to select rows from out of complete result set is called Selection. It involves conditional filtering and data staging. The subset can range from no r...
SELECT DISTINCT agent_code, ord_amount, cust_code, ord_num: This line specifies that you want to retrieve unique combinations of 'agent_code', 'ord_amount', 'cust_code', and 'ord_num'. The DISTINCT keyword ensures that only unique combinations are returned; any duplicate combinations will ...
1. PROC SQL eliminates duplicate (nonunique) rows in the tables. 2. PROC SQL selects the rows that meet the criteria and, where requested, overlays columns. 当进行的操作同时需要展现unique和duplicate行时则只会进行第二步,忽略第一步。
SELECT DISTINCT vs SELECT TheSELECT DISTINCTstatement is used when you want to return only unique (distinct) values in the result set. Whereas, a regularSELECTstatement without theDISTINCTkeyword retrieves all rows from the specified columns, including duplicate values. ...
ROW_NUMBER WF enumerates the rows. We can also use it to remove duplicate records with it. Or to take a random sample. As the name suggests WF can calculate statistics on a given window: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 ...
of three tables that all have the same five rows of data. The first example usesUNION ALLto show the duplicated records, and returns all 15 rows. The second example usesUNIONwithoutALLto eliminate the duplicate rows from the combined results of the threeSELECTstatements, and returns five rows...
非SELECT语句的select_type值显示受影响表的语句类型。例如,DELETE语句的select_type是DELETE。 table (JSON名称: table_name) 输出行引用的表的名称。这也可以是以下值之一: :该行引用具有id值为M和N的行的联合。 :该行引用id值为N的行的派生表结果。派生表可能是由FROM子句中的子查询产生的。
CREATE TABLE TestBatch (ColA INT PRIMARY KEY, ColB CHAR(3)); GO INSERT INTO TestBatch VALUES (1, 'aaa'); INSERT INTO TestBatch VALUES (2, 'bbb'); INSERT INTO TestBatch VALUES (1, 'ccc'); -- Duplicate key error. GO SELECT * FROM TestBatch; -- Returns rows 1 ...