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The SQL From clause is the source of a rowset to be operated upon in a Data Manipulation Language (DML) statement. From clauses are very common, and will provide the rowset to be exposed through a Select statement, the source of values in an Update statement, and the target rows to be deleted in a Delete statement. FROM is an SQL reserved word in the SQL standardThe FROM clause is used in conjunction with SQL statements, and takes the following general form:''SQL-DML-Statement'' FROM ''table_name'' WHERE ''predicate'' The From clause can generally be anything that returns a rowset, a table, view, function, or system-provided information like the Information Schema, which is typically running proprietary commands and returning the information in a table form.〔(【引用サイトリンク】title=The FROM Clause )〕 ==Examples== The following query returns only those rows from table ''mytable'' where the value in column ''mycol'' is greater than 100. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「From (SQL)」の詳細全文を読む スポンサード リンク
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