Database Articles - Page 222 of 618

To find a match, use regular expressions in MySQL. Let us first create a table −mysql> create table DemoTable    -> (    -> Value varchar(60)    -> ); Query OK, 0 rows affected (0.48 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('8|56|78|45'); Query OK, 1 row affected (0.24 sec) mysql> insert into DemoTable values('9876'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('98|8'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('3|8|9'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('97|94'); Query OK, 1 ... Read More

To insert records with double quotes, use a backslash (\) as in the below syntax −Syntaxinsert into yourTableName values('\"yourValue\"');Let us first create a table −mysql> create table DemoTable    -> (    -> Name varchar(20)    -> ); Query OK, 0 rows affected (0.63 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('\"John\"'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('\"Chris\"'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('\"Adam Smith\"'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('\"Carol\"'); Query OK, 1 row affected ... Read More

Let us first create a table −mysql> create table DemoTable    -> (    -> ListOfName text    -> ); Query OK, 0 rows affected (0.66 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Carol, Sam, John, David, Bob, Mike, Robert, John, Chris, James, Jace'); Query OK, 1 row affected (0.13 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+------------------------------------------------------------+ | ListOfName                                               ... Read More

To extract date from the string in MySQL, use SUBSTRING_INDEX(). Let us first create a table −mysql> create table DemoTable    -> (    -> Title text    -> ); Query OK, 0 rows affected (0.58 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John has got joining date.12/31/2018'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('Carol has got joining date.01/11/2019'); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable values('Sam will arrive at.12/03/2050'); Query OK, 1 row affected (0.87 sec)Display all records from the table using select statement ... Read More

Use MySQL GROUP_BY to find the number of occurrences from two columns. Let us first create a table −mysql> create table DemoTable    -> (    -> Name1 varchar(20),    -> Name2 varchar(20)    -> ); Query OK, 0 rows affected (0.61 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John', 'Adam'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('Chris', 'David'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('Robert', 'Mike'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable values('David', 'Chris'); Query OK, 1 row ... Read More

Let us first create a table −mysql> create table DemoTable    -> (    -> Date1 date,    -> Date2 date    -> ); Query OK, 0 rows affected (1.04 sec)Insert some records in the table using insert command &miuns;mysql> insert into DemoTable values('2017-01-10', '2017-12-10'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('2018-12-31', '2015-01-02'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('2020-03-01', '2019-06-15'); Query OK, 1 row affected (0.19 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+------------+------------+ | Date1     ... Read More

For the current date, use CURDATE(). Also, use STR_TO_DATE() to format date and compare it with the current date as in the below syntax −Syntaxselect *from yourTableName where str_to_date(yourColumnName, 'yourFormatSpecifier')=curdate();Let’s say the current date is 27/10/2019.Let us first create a table −mysql> create table DemoTable    -> (    -> JoiningDate varchar(40)    -> ); Query OK, 0 rows affected (0.79 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('27/10/2017'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('27/10/2018'); Query OK, 1 row affected (0.78 sec) mysql> insert into DemoTable values('27/10/2019'); Query ... Read More

For this, you can use ORDER BY FIELD. Let us first create a table −mysql> create table DemoTable    -> (    -> Id int,    -> Name varchar(20)    -> ); Query OK, 0 rows affected (1.78 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(101, 'Chris'); Query OK, 1 row affected (0.38 sec) mysql> insert into DemoTable values(201, 'Mike'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(110, 'Adam'); Query OK, 1 row affected (0.52 sec) mysql> insert into DemoTable values(250, 'John'); Query OK, 1 row affected (0.33 sec)Display all ... Read More

For this, use UNION more than once in a single MySQL query. Let us first create a table −mysql> create table DemoTable    -> (    -> Value1 int,    -> Value2 int,    -> Value3 int    -> ); Query OK, 0 rows affected (0.69 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(20, null, null); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values(20, null, null); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values(20, null, null); Query OK, 1 row affected (0.12 sec) mysql> insert into ... Read More

CASE statement with the WHEN clause is used to work around conditions. Following is the syntax−select *,    case when yourCondition then yourStatement    when yourCondition then yourStatement    .    . else yourStatement from yourTableName;Let us first create a table −mysql> create table DemoTable    -> (    -> StudentName varchar(20),    -> StudentMarks int    -> ); Query OK, 0 rows affected (0.77 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris', 78); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values('Robert', 88); Query OK, 1 row affected (0.14 sec) ... Read More