Related knowledge about SQL SELECT statement

SQL SELECT statement is very important in database operation. This article will explain it.

SQL SELECT statement

The SELECT statement is used to select data from a table.

The results are stored in a results table (called a result set).

SQL SELECT syntax

SELECT column name FROM table name

and:

SELECT * FROM table name

Note: SQL statements are not case sensitive. SELECT is equivalent to select.

SQL SELECT Example

To get the contents of the columns named "LastName" and "FirstName" (from the database table named "Persons"), use a SELECT statement similar to this ：

SELECT LastName,FirstName FROM Persons

SQL SELECT * Example

Now we want to select all columns from the "Persons" table.

Please use the symbol * instead of column names, like this:

SELECT * FROM Persons

Tip: The asterisk (*) selects all columns A shortcut.

The results obtained by the SQL Query program are stored in a result set. Most database software systems allow programmingfunctionsnavigation in the result set, such as: Move-To-First-Record, Get-Record-Content, Move-To-Next-Record and so on.

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