How do you write a SELECT statement in PL SQL?

PL/SQL SELECT INTO examples

1. First, declare a variable l_customer_name whose data type anchors to the name columns of the customers table.
2. Second, use the SELECT INTO statement to select value from the name column and assign it to the l_customer_name variable.
3. Third, show the customer name using the dbms_output.

What is SELECT into in Oracle?

The SELECT INTO statement retrieves data from one or more database tables, and assigns the selected values to variables or collections. For a full description of the SELECT statement, see Oracle Database SQL Reference. INTO ), this statement retrieves one or more columns from a single row.

When using the SELECT statement in PL SQL The INTO clause is required and queries can return one or more rows?

In each example so far, the restriction defined in the query’s WHERE clause has been based on a primary key. Using a unique or primary key is important as the SELECT INTO clause can not retrieve more that one row of data. If the query returns more that one row an exception is thrown.

What is SELECT into statement?

The SQL Server (Transact-SQL) SELECT INTO statement is used to create a table from an existing table by copying the existing table’s columns. It is important to note that when creating a table in this way, the new table will be populated with the records from the existing table (based on the SELECT Statement).

What is the purpose of select statement in PL SQL?

The SELECT INTO statement retrieves data from one or more database tables, and assigns the selected values to variables or collections. For a full description of the SELECT SQL statement, see Oracle Database SQL Reference.

What is cursor in PL SQL with examples?

A cursor is a pointer to this context area. PL/SQL controls the context area through a cursor. A cursor holds the rows (one or more) returned by a SQL statement. The set of rows the cursor holds is referred to as the active set.

What is the purpose of SELECT statement in PL SQL?

How does select into work?

The SELECT INTO statement is a query that allows you to create a new table and populate it with the result set of a SELECT statement . To add data to an existing table, see the INSERT INTO statement instead. SELECT INTO can be used when you are combining data from several tables or views into a new table.

How do you select a variable in SQL?

SELECT @local_variable is typically used to return a single value into the variable. However, when expression is the name of a column, it can return multiple values. If the SELECT statement returns more than one value, the variable is assigned the last value that is returned.

How do you execute a PL SQL procedure?

Executing a Standalone Procedure

1. Using the EXECUTE keyword.
2. Calling the name of the procedure from a PL/SQL block.

When should a close statement be used in PL SQL?

After all rows have been retrieved from the result set that is associated with a cursor, the cursor must be closed. The result set cannot be referenced after the cursor has been closed. However, the cursor can be reopened and the rows of the new result set can be fetched.

Why cursors are used in PL SQL?

The major function of a cursor is to retrieve data, one row at a time, from a result set, unlike the SQL commands which operate on all the rows in the result set at one time. Cursors are used when the user needs to update records in a singleton fashion or in a row by row manner, in a database table.

What does select all mean in SQL?

SQL – Select All (*) “SELECT (*)” is a shortcut that can be used to select all table columns rather than listing each of them by name. Unfortunately, going this route doesn’t allow for you to alter the presentation of the results.

What is a SELECT CASE statement?

A Select Case statement allows a variable to be tested for equality against a list of values. Each value is called a case, and the variable being switched on is checked for each select case.

What is SELECT query in SQL?

SQL – SELECT Query. The SQL SELECT statement is used to fetch the data from a database table which returns this data in the form of a result table. These result tables are called result-sets.

Where statement in SQL query?

WHERE is an SQL reserved word. The WHERE clause is used in conjunction with SQL DML statements, and takes the following general form: SQL-DML-Statement FROM table_name WHERE predicate. all rows for which the predicate in the WHERE clause is True are affected (or returned) by the SQL DML statement or query.