Found 4219 Articles for MySQLi

To select a column name with spaces, use the back tick symbol with column name. The symbol is ( ` `). Back tick is displayed in the keyboard below the tilde operator ( ~).Firstly, create a table −mysql> CREATE table SpaceColumn -> ( -> `Student Name` varchar(100) -> ); Query OK, 0 rows affected (0.48 sec)Inserting recordsmysql> INSERT into SpaceColumn values('John'); Query OK, 1 row affected (0.18 sec) mysql> INSERT into SpaceColumn values('Bob'); Query OK, 1 row affected (0.17 sec)The syntax to get column name with space is as follows −SELECT `column_name` from yourTableName; Now I will apply the ... Read More

Firstly, we will create a table with the help of CREATE command.Creating a table −mysql> CREATE table InCaseSensDemo -> ( -> Name varchar(100) -> ); Query OK, 0 rows affected (0.50 sec)Inserting records into the table with the help of INSERT command −mysql> INSERT into InCaseSensDemo values('JOhN'); Query OK, 1 row affected (0.11 sec) mysql> INSERT into InCaseSensDemo values('bob'); Query OK, 1 row affected (0.21 sec) mysql> INSERT into InCaseSensDemo values('BoB'); Query OK, 1 row affected (0.13 sec) mysql> INSERT into InCaseSensDemo values('Bob'); Query OK, 1 row affected (0.18 sec)Displaying all the records with the help of ... Read More

We can do this with the help of lower() with column name. Firstly, we will create a table with the help of CREATE command.Creating a table −mysql> CREATE table InCaseSensDemo -> ( -> Name varchar(100) -> ); Query OK, 0 rows affected (0.50 sec)Inserting records into the table with the help of INSERT command −mysql> INSERT into InCaseSensDemo values('JOhN'); Query OK, 1 row affected (0.11 sec) mysql> INSERT into InCaseSensDemo values('bob'); Query OK, 1 row affected (0.21 sec) mysql> INSERT into InCaseSensDemo values('BoB'); Query OK, 1 row affected (0.13 sec) mysql> INSERT into InCaseSensDemo values('Bob'); Query OK, ... Read More

SELECT DISTINCT can be used to give distinct values. Use it to remove duplicate records and it can be used with aggregate function as well. For example: MAX, AVG etc. This can be applied on a single column.Now, I am creating a table to use SELECT DISTINCT for a column. Creating a table with the help of CREATE command −mysql> CREATE TABLE DistinctDemo -> ( -> id int, -> name varchar(100) -> ); Query OK, 0 rows affected (0.64 sec)Inserting records −mysql> INSERT into DistinctDemo values(1, 'John'); Query OK, 1 row affected (0.17 sec) mysql> INSERT into DistinctDemo values(2, ... Read More

To add 1 day, use date_add() function. Adding a day to datetime in MySQL gives the next day. The following is the syntax −SELECT DATE_ADD('Any date’', INTERVAL 1 DAY) AS AliasName;Now, I am applying the above query to add a day with date in MySQL. The query is as follows −mysql> SELECT DATE_ADD('2018-10-08', INTERVAL 1 DAY) AS NextDay; After executing the above query, we will get the following output −+------------+ | NextDay | +------------+ | 2018-10-09 | +------------+ 1 row in set (0.00 sec)Therefore, in this sample output, I am adding a day with current date

To enable query log, use the command SET global. You cannot use set general_log in MySQL version 8.0.12 version. If you are using version 8.0.12, then you will get the below given error. Here, we are trying to set general_log to see what error will come −mysql> SET general_log = 1;The following is the output −ERROR 1229 (HY000): Variable 'general_log' is a GLOBAL variable and should be set with SET GLOBAL Now, we will use the global command with general_log. The query is as follows −mysql> SET global general_log = 1; Query OK, 0 rows affected (0.10 sec)To check it ... Read More

Unsigned allows us to enter positive value; you cannot give any negative number. Let us create a table to understand unsigned in MySQL. To create a table, we will use the CREATE command.Let us create a table −mysql> CREATE table UnsignedDemo -> ( -> id int unsigned -> ); Query OK, 0 rows affected (0.61 sec)After that I will insert only positive values. Let us insert some records −mysql> INSERT into UnsignedDemo values(124); Query OK, 1 row affected (0.09 sec) mysql> INSERT into UnsignedDemo values(78967); Query OK, 1 row affected (0.14 sec)I am displaying all the records with the ... Read More

To know the current auto_increment value, we can use the last_insert_id() function. Firstly, we will create a table with the help of INSERT command.Creating a table −mysql> CREATE table AutoIncrement -> ( -> IdAuto int auto_increment, -> primary key(IdAuto) -> ); Query OK, 0 rows affected (0.59 sec)After creating a table, we will insert the records with the help of INSERT command. Inserting records −mysql> INSERT into AutoIncrement values(); Query OK, 1 row affected (0.48 sec) mysql> INSERT into AutoIncrement values(); Query OK, 1 row affected (0.17 sec) mysql> INSERT into AutoIncrement values(); Query OK, 1 row affected ... Read More

To know the current time, we can use the now() function with SELECT statement. The query is as follows −mysql> SELECT now();After executing the above query, we will get the current time. The following is the output −+---------------------+ | now() | +---------------------+ | 2018-10-06 12:57:25 | +---------------------+ 1 row in set (0.02 sec)To set the time zone, we can use the command SET. The syntax is as follows −mysql> SET time_zone = "Some value"; Now I am applying the above query to set the time zone. ... Read More

In MySQL, the length of NULL is 0. Here, we will see how NULL can be used with SELECT statement. Let us create a table with the help of CREATE command −Creating a table −mysql> CREATE table NullWIthSelect -> ( -> Name varchar(100) -> ); Query OK, 0 rows affected (0.62 sec)Above, I have created a table successfully. Now I will insert some records with the help of INSERT command −Inserting records −mysql> INSERT into NullWIthSelect values('John'); Query OK, 1 row affected (0.16 sec) mysql> INSERT into NullWIthSelect values('Bob'); Query OK, 1 row affected (0.12 sec) mysql> INSERT ... Read More