A table constructor returns a table of one or more columns.
When there is only one column, the name of the column is Value.
When there are N columns where N > 1, the names of the columns from left to right are Value1, Value2, …, ValueN.

{ <scalarExpr1>, <scalarExpr2>, … } 
{ ( <scalarExpr1>, <scalarExpr2>, … ), ( <scalarExpr1>, <scalarExpr2>, … ), … }

The first syntax returns a table of a single column. The second syntax returns a table of one or more columns.
The number of scalar expressions must be the same for all rows.
When the data types of the values for a column are different in different rows, all values are converted to a common data type.