Which of the following is a valid SQL statement?

Question

Which of the following is a valid SQL statement?​

BlackTom AI · Accepted Answer

Question: Which of the following is a valid SQL statement?

Option 1: 'CREATE TABLE newname (colA NUMBER, colB DATE);' This follows the standard CREATE TABLE syntax, listing the table name and a list of column definitions with data types. In Oracle-like dialects, NUMBER and DATE are valid data types, and the parentheses correctly enclose the column definitions.

Option 2: 'CREATE TABLE newname SELECT all FROM books;' This blends CREATE TABLE with a SELECT clause in a way that is not valid SQL syntax. If you want to create a table from a query, you typically use 'CREATE TABLE newname AS SELECT ...' or use 'CREATE TABLE newname AS SELECT ...' in some systems, but the exact form here is incorrect.

Option 3: 'CREATE TABLE newname (colA, colB);' Here, the column definitions specify names but omit data types. SQL requires each column to have an associated data type, so this is incomplete and invalid.

Option 4: 'CREATE TABLE newname (colA DATE, colB VARCHAR2(7,2));' This attempts to declare a VARCHAR2 with a precision or scale inside the type declaration as '(7,2)'. VARCHAR2 uses a single length parameter like VARCHAR2(7); specifying both precision and scale is invalid for VARCHAR2. Depending on the dialect, (7,2) is used for numeric types like NUMBER, not for character types.

Overall, the first option correctly adheres to the required CREATE TABLE format with valid data types, while the other options mix in incorrect syntax, missing types, or invalid type parameters.

Which of the following is a valid SQL statement?单项选择题

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