Declaring column types and constraints in the grid, value checking and the DDL created per engine. A TABLE tab is a grid you fill in to CREATE a database table. Row 1 holds the column NAMES, typed like any other cell. Each column header carries a button showing the column's declared TYPE; clicking it opens the type list and the three constraints — Required (NOT NULL), Primary key, Unique. From row 2 down, every value is checked against the declared type AS IT IS TYPED: a value that does not fit is refused rather than stored, and the status bar says why, naming the column, the type and the value.
This site needs JavaScript for the full experience. Every page above is reachable without it.