Angular 2 offers developers two technologies for building forms: template-driven forms and reactive forms. Both technologies are part of the @angular/forms
library and contain the same set of form control classes. At the same time, they offer different programming styles and techniques and refer to different modules: FormsModule
and ReactiveFormsModule
, respectively.
JOIN, UNION, INTERSECT and EXCEPT in SQL
Joining tables in a SELECT query is done using the JOIN statement.
Grouping in SQL: GROUP BY clause, HAVING clause and aggregate functions
The GROUP BY clause (SELECT statement) allows you to group data (rows) by the value of a column or multiple columns or expressions. The result will be a set of summary rows.
Continue reading Grouping in SQL: GROUP BY clause, HAVING clause and aggregate functions
INSERT, UPDATE and DELETE in SQL
SQL uses INSERT, UPDATE, and DELETE statements to modify data.
SELECT in SQL
Select – performs a selection (extraction of individual rows) and/or a projection (extraction of individual columns) of the data and returns the result set.
Simple option:
1 2 | SELECT [ALL | DISTINCT] column_list FROM {table1 [tab_aliasl]},... |