MariaDB [(none)]> create database Fechhas; Query OK, 1 row affected (0.002 sec) MariaDB [(none)]> create table estudiante(Carnet varchar(3) primary key not null, -> Nombre varchar(50) not null, -> Fechamatricula datetime, -> Fechanacimineto datetime, -> Sexo varchar(10)); ERROR 1046 (3D000): No database selected MariaDB [(none)]> use Fechhas; Database changed MariaDB [Fechhas]> create table estudiante(Carnet varchar(3) primary key not null, -> Nombre varchar(50) not null, -> Fechamatricula datetime, -> Fechanacimineto datetime, -> Sexo varchar(10)); Query OK, 0 rows affected (0.011 sec) MariaDB [Fechhas]> describe estudiante; +-----------------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-----------------+-------------+------+-----+---------+-------+ | Carnet | varchar(3) | NO | PRI | NULL | | | Nombre | varchar(50) | NO | | NULL | | | Fechamatricula | datetime | YES | | NULL | | | Fechanacimineto | datetime | YES | | NULL | | | Sexo | varchar(10) | YES | | NULL | | +-----------------+-------------+------+-----+---------+-------+ 5 rows in set (0.013 sec) MariaDB [Fechhas]> create table materia(CodigoM varchar(3) primary key not null, -> Descripcion varchar(50) not null, -> Valor int(10) not null); Query OK, 0 rows affected (0.012 sec) MariaDB [Fechhas]> describe materia; +-------------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------------+-------------+------+-----+---------+-------+ | CodigoM | varchar(3) | NO | PRI | NULL | | | Descripcion | varchar(50) | NO | | NULL | | | Valor | int(10) | NO | | NULL | | +-------------+-------------+------+-----+---------+-------+ 3 rows in set (0.012 sec) MariaDB [Fechhas]> create table estmat(Carnet varchar(3) not null, -> CodigoM varchar(3) not null); Query OK, 0 rows affected (0.010 sec) MariaDB [Fechhas]> describe estmat; +---------+------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +---------+------------+------+-----+---------+-------+ | Carnet | varchar(3) | NO | | NULL | | | CodigoM | varchar(3) | NO | | NULL | | +---------+------------+------+-----+---------+-------+ 2 rows in set (0.013 sec) MariaDB [Fechhas]> insert into estudiante (Carnet, Nombre, Fechamatricula, Fechanacimiento, Sexo)values('001','maria','2010-01-15','1966-05-13','f'), -> ; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '' at line 1 MariaDB [Fechhas]> insert into estudiante (Carnet, Nombre, Fechamatricula, Fechanacimineto, Sexo)values('001','maria','2010-01-15','1966-05-13','f'), -> ('002','juana','2010-06-08','1973-01-22','f'), -> ('003','carlos','2010-06-28','1976-03-05','m'), -> ('004','maria parra','2010-06-11','1976-08-15','f'), -> ('005','pablo neruda','2011-02-13','1990-08-25','m'), -> ('006','bladimir palacio','2011-02-04','1994-09-03','m'), -> ('007','apolonia serrano','2011-02-28','1994-03-09','f'), -> ('008','federico serrano','2011-03-05','1991-06-10','m'); Query OK, 8 rows affected (0.004 sec) Records: 8 Duplicates: 0 Warnings: 0 MariaDB [Fechhas]> select * from estudiante; +--------+------------------+---------------------+---------------------+------+ | Carnet | Nombre | Fechamatricula | Fechanacimineto | Sexo | +--------+------------------+---------------------+---------------------+------+ | 001 | maria | 2010-01-15 00:00:00 | 1966-05-13 00:00:00 | f | | 002 | juana | 2010-06-08 00:00:00 | 1973-01-22 00:00:00 | f | | 003 | carlos | 2010-06-28 00:00:00 | 1976-03-05 00:00:00 | m | | 004 | maria parra | 2010-06-11 00:00:00 | 1976-08-15 00:00:00 | f | | 005 | pablo neruda | 2011-02-13 00:00:00 | 1990-08-25 00:00:00 | m | | 006 | bladimir palacio | 2011-02-04 00:00:00 | 1994-09-03 00:00:00 | m | | 007 | apolonia serrano | 2011-02-28 00:00:00 | 1994-03-09 00:00:00 | f | | 008 | federico serrano | 2011-03-05 00:00:00 | 1991-06-10 00:00:00 | m | +--------+------------------+---------------------+---------------------+------+ 8 rows in set (0.001 sec) MariaDB [Fechhas]> insert into materia(CodigoM, Descripcion, Valor)values('001','programa I','32000'), -> ('002','programa II','328000'), -> ('003','programa III','40000'), -> ('004','matematicas','30000'), -> ('005','inglT','30000'); Query OK, 5 rows affected (0.006 sec) Records: 5 Duplicates: 0 Warnings: 0 MariaDB [Fechhas]> select * from materia; +---------+--------------+--------+ | CodigoM | Descripcion | Valor | +---------+--------------+--------+ | 001 | programa I | 32000 | | 002 | programa II | 328000 | | 003 | programa III | 40000 | | 004 | matematicas | 30000 | | 005 | inglT | 30000 | +---------+--------------+--------+ 5 rows in set (0.000 sec) MariaDB [Fechhas]> insert into estmat(Carnet, CodigoM)values('001','003'); Query OK, 1 row affected (0.007 sec) MariaDB [Fechhas]> insert into estmat(Carnet, CodigoM)values('001','005'), -> ('002','002'), -> ('002','003'), -> ('002','004'), -> ('003','004'), -> ('003','001'), -> ('004','004'), -> ('004','005'), -> ('005','002'), -> ('005','005'), -> ('006','001'), -> ('006','005'), -> ('007','003'), -> ('007','004'), -> ('008','001'), -> ('008','004'), -> ('008','005'); Query OK, 17 rows affected (0.010 sec) Records: 17 Duplicates: 0 Warnings: 0 MariaDB [Fechhas]> select * from estmat; +--------+---------+ | Carnet | CodigoM | +--------+---------+ | 001 | 003 | | 001 | 005 | | 002 | 002 | | 002 | 003 | | 002 | 004 | | 003 | 004 | | 003 | 001 | | 004 | 004 | | 004 | 005 | | 005 | 002 | | 005 | 005 | | 006 | 001 | | 006 | 005 | | 007 | 003 | | 007 | 004 | | 008 | 001 | | 008 | 004 | | 008 | 005 | +--------+---------+ 18 rows in set (0.001 sec) MariaDB [Fechhas]> select count(*) from estudiante where year(Fechanacimineto) between 1970 and 1979; +----------+ | count(*) | +----------+ | 3 | +----------+ 1 row in set (0.001 sec) MariaDB [Fechhas]> Select * from estudiante where fechanacimineto between '1999-01-01' and '2003-12-31'; Empty set (0.001 sec) MariaDB [Fechhas]> Select nombre From estudiante Where Year(Current_date()) - year(FechanaciminEto) > 25; +------------------+ | nombre | +------------------+ | maria | | juana | | carlos | | maria parra | | pablo neruda | | bladimir palacio | | apolonia serrano | | federico serrano | +------------------+ 8 rows in set (0.001 sec) MariaDB [Fechhas]> Select carnet, Nombre, Year(Current_date()) - year(FechanaciminEto) 'Edad' From estudiante; +--------+------------------+------+ | carnet | Nombre | Edad | +--------+------------------+------+ | 001 | maria | 57 | | 002 | juana | 50 | | 003 | carlos | 47 | | 004 | maria parra | 47 | | 005 | pablo neruda | 33 | | 006 | bladimir palacio | 29 | | 007 | apolonia serrano | 29 | | 008 | federico serrano | 32 | +--------+------------------+------+ 8 rows in set (0.001 sec) MariaDB [Fechhas]> select codigom, descripcion, valor, if(valor > 300000, 'Cara', 'Economica') As 'Categoria' from materia; +---------+--------------+--------+-----------+ | codigom | descripcion | valor | Categoria | +---------+--------------+--------+-----------+ | 001 | programa I | 32000 | Economica | | 002 | programa II | 328000 | Cara | | 003 | programa III | 40000 | Economica | | 004 | matematicas | 30000 | Economica | | 005 | inglT | 30000 | Economica | +---------+--------------+--------+-----------+ 5 rows in set (0.001 sec) MariaDB [Fechhas]> select codigom, descripcion, valor, if(valor > 200000 and valor <= 300000, 'Economica', if(valor > 300000, 'Cara', 'Otro')) As 'Categoria' from materia; +---------+--------------+--------+-----------+ | codigom | descripcion | valor | Categoria | +---------+--------------+--------+-----------+ | 001 | programa I | 32000 | Otro | | 002 | programa II | 328000 | Cara | | 003 | programa III | 40000 | Otro | | 004 | matematicas | 30000 | Otro | | 005 | inglT | 30000 | Otro | +---------+--------------+--------+-----------+ 5 rows in set (0.001 sec) MariaDB [Fechhas]> exit