SELECT first_name, last_name FROM student_details; You can also use clauses like WHERE, GROUP BY, HAVING, ORDER BY with SELECT statement. We will discuss these commands in coming chapters. NOTE: In a SQL SELECT statement only SELECT and FROM statements are mandatory. Other clauses like ...
Data retrieval from data base is done through appropriate and efficient use of SQL. Three concepts from relational theory encompass the capability of the SELECT statement: projection, selection, and joining. Projection(投影): A project operation selects only certain columns (fields) from a table. ...
In SQL, the SELECT INTO statement is used to copy data from one table to another. Example -- copy all the contents of a table to a new table SELECT * INTO CustomersCopy FROM Customers; Here, the SQL command copies all data from the Customers table to the new CustomersCopy table. ...
[ WITH with_query [, ...] ] SELECT [ ALL | DISTINCT ] select_expr [, ...] [ FROM from_item [, ...] ] [ WHERE condition ] [ GROUP BY [ ALL | DISTINCT ] grouping_element [, ...] ] [ HAVING condition] [ WINDOW window_name AS ( window_definition ) [, ...] ] [ { ...
Let’s take a look at each of the keywords within the SELECT statement. SELECT The SELECT clause of the SELECT statement refers to the first line. It includes the word SELECT and anything that comes after the SELECT up until the next keyword, which is either INTO or FROM. ...
The SELECT INTO statement copies data from one table into a new table.SELECT INTO SyntaxCopy all columns into a new table:SELECT * INTO newtable [IN externaldb] FROM oldtableWHERE condition; Copy only some columns into a new table:
LOCKED]|LOCKINSHARE MODE]]SELECTisusedtoretrieve rows selectedfromoneormore tables,andcan includeUNIONstatementsandsubqueries. See[HELP UNION],andhttp://dev.mysql.com/doc/refman/8.0/en/subqueries.html. ASELECTstatement can startwithaWITHclausetodefine commontableexpressions accessible within theSELECT....
Java Statement 执行插入sql的返回结果 java执行select Java SE基础(三)流程控制 概述 顺序结构 选择结构 if-else语句 switch-case语句 循环结构 for语句 while语句 do-while语句 注意 死循环与跳转控制语句 概述 流程控制就是使用流程控制语句来控制程序的执行流程。Java程序的执行流程分为:顺序结构、选择结构、循环...
SELECT UnitPrice, OrderQty, UnitPrice * OrderQty AS Total FROM Purchasing.PurchaseOrderDetail The bit ” UnitPrice * OrderQty” says to multiply UnitPrice by Quantity. SQL Distinct So far we have used the select statement to retrieve all the records in a table regardless if some values repea...
TheSELECTstatement is used to select data from a database. Example Return data from the Customers table: SELECTCustomerName, CityFROMCustomers; Try it Yourself » Syntax SELECTcolumn1,column2, ... FROMtable_name; Here, column1, column2, ... are thefield namesof the table you want to ...