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Setting environment for using XAMPP for Windows.
nelly@NELLYIVANOVA c:\xampp
# mysql -uroot
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 16
Server version: 10.4.21-MariaDB mariadb.org binary distribution

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [(none)]> create database statements;
Query OK, 1 row affected (0.007 sec)

MariaDB [(none)]> use statements;
Database changed
MariaDB [statements]> create table t1 (a int,b char(10));
Query OK, 0 rows affected (0.015 sec)

MariaDB [statements]> insert into t1 values (1,"one"),(2, "two"),(3,"three");
Query OK, 3 rows affected (0.010 sec)
Records: 3  Duplicates: 0  Warnings: 0

MariaDB [statements]> prepare test from "select * from t1 where a=?";
Query OK, 0 rows affected (0.003 sec)
Statement prepared

MariaDB [statements]> set @param=2;
Query OK, 0 rows affected (0.006 sec)

MariaDB [statements]> execute test using @param;
+------+------+
| a    | b    |
+------+------+
|    2 | two  |
+------+------+
1 row in set (0.012 sec)

MariaDB [statements]> set @param=3;
Query OK, 0 rows affected (0.000 sec)

MariaDB [statements]> execute test using @param;
+------+-------+
| a    | b     |
+------+-------+
|    3 | three |
+------+-------+
1 row in set (0.000 sec)

MariaDB [statements]> deallocate prepare test;
Query OK, 0 rows affected (0.006 sec)

MariaDB [statements]> PREPARE stmt1 FROM 'SELECT SQRT(POW(?,2) + POW(?,2)) AS hypotenuse';
Query OK, 0 rows affected (0.008 sec)
Statement prepared

MariaDB [statements]> SET @a = 3;
Query OK, 0 rows affected (0.000 sec)

MariaDB [statements]> SET @b = 4;
Query OK, 0 rows affected (0.000 sec)

MariaDB [statements]> EXECUTE stmt1 USING @a, @b;
+------------+
| hypotenuse |
+------------+
|          5 |
+------------+
1 row in set (0.006 sec)

MariaDB [statements]> DEALLOCATE PREPARE stmt1;
Query OK, 0 rows affected (0.000 sec)

MariaDB [statements]> SET @s = 'SELECT SQRT(POW(?,2) + POW(?,2)) AS hypotenuse';
Query OK, 0 rows affected (0.001 sec)

MariaDB [statements]> PREPARE stmt2 FROM @s;
Query OK, 0 rows affected (0.000 sec)
Statement prepared

MariaDB [statements]> SET @a = 6;
Query OK, 0 rows affected (0.000 sec)

MariaDB [statements]> SET @b = 8;
Query OK, 0 rows affected (0.000 sec)

MariaDB [statements]> EXECUTE stmt2 USING @a, @b;
+------------+
| hypotenuse |
+------------+
|         10 |
+------------+
1 row in set (0.000 sec)

MariaDB [statements]> DEALLOCATE PREPARE stmt2;
Query OK, 0 rows affected (0.000 sec)

MariaDB [statements]> CREATE TABLE t1 (a INT NOT NULL);
ERROR 1050 (42S01): Table 't1' already exists
MariaDB [statements]> INSERT INTO t1 VALUES (4), (8), (11), (32), (80);
ERROR 1136 (21S01): Column count doesn't match value count at row 1
MariaDB [statements]> SET @table = 't1';
Query OK, 0 rows affected (0.000 sec)

MariaDB [statements]> SET @s = CONCAT('SELECT * FROM ', @table);
Query OK, 0 rows affected (0.007 sec)

MariaDB [statements]> PREPARE stmt3 FROM @s;
Query OK, 0 rows affected (0.000 sec)
Statement prepared

MariaDB [statements]> EXECUTE stmt3;
+------+-------+
| a    | b     |
+------+-------+
|    1 | one   |
|    2 | two   |
|    3 | three |
+------+-------+
3 rows in set (0.001 sec)

MariaDB [statements]> CREATE TABLE t2 (a INT NOT NULL);
Query OK, 0 rows affected (0.015 sec)

MariaDB [statements]> INSERT INTO t2 VALUES (4), (8), (11), (32), (80);
Query OK, 5 rows affected (0.009 sec)
Records: 5  Duplicates: 0  Warnings: 0

MariaDB [statements]> SET @table = 't2';
Query OK, 0 rows affected (0.000 sec)

MariaDB [statements]> SET @s = CONCAT('SELECT * FROM ', @table);
Query OK, 0 rows affected (0.000 sec)

MariaDB [statements]> PREPARE stmt3 FROM @s;
Query OK, 0 rows affected (0.000 sec)
Statement prepared

MariaDB [statements]> EXECUTE stmt3;
+----+
| a  |
+----+
|  4 |
|  8 |
| 11 |
| 32 |
| 80 |
+----+
5 rows in set (0.001 sec)

MariaDB [statements]> DEALLOCATE PREPARE stmt3;
Query OK, 0 rows affected (0.000 sec)

MariaDB [statements]>