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Let us first create a table −mysql> create table DemoTable -> ( -> Value int -> ); Query OK, 0 rows affected (0.80 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(10); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values(20); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values(100); Query OK, 1 row affected (0.14 sec)Display all records from the table using select statement −mysql> select *from DemoTable;OutputThis will produce the following output −+-------+ | Value | +-------+ | 10 | | ... Read More
To order by number of chars, use ORDER BY and LENGTH() method. Following is the syntax −select *from yourTableName order by LENGTH(yourColumnName) DESC;Let us first create a table −mysql− create table DemoTable -> ( -> Name varchar(100) -> ); Query OK, 0 rows affected (0.50 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values('Robert'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('Bob'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable ... Read More
Use group_concat() function from MySQL to concatenate. Let us first create a table −mysql> create table DemoTable -> ( -> Subject varchar(10) -> ); Query OK, 0 rows affected (0.43 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('C'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values('C++'); Query OK, 1 row affected (0.25 sec) mysql> insert into DemoTable values('C++'); Query OK, 1 row affected (0.06 sec) mysql> insert into DemoTable values('MongoDB'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('MySQL'); Query ... Read More
If you want to get only digits using REGEXP, use the following regular expression( ^[0-9]*$) in where clause.Case 1 − If you want only those rows which have exactly 10 digits and all must be only digit, use the below regular expression.SELECT *FROM yourTableName WHERE yourColumnName REGEXP '^[0-9]{10}$';Case 2 − If you want only those rows with the digit either 1 or more, the following is the syntax −SELECT *FROM yourTableName WHERE yourColumnName REGEXP '^[0-9]*$';The above syntax will give only those rows that do not have any any characters.To understand the above syntax, let us create a table. The query ... Read More
Use FIND_IN_SET for this. Let us first create a table −mysql> create table DemoTable -> ( -> ListOfValues text -> ); Query OK, 0 rows affected (0.56 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('10|20|30|40|50|60|100'); Query OK, 1 row affected (0.18 sec)Display all records from the table using select statement −mysql> select *from DemoTable;OutputThis will produce the following output −+-----------------------+ | ListOfValues | +-----------------------+ | 10|20|30|40|50|60|100 | +-----------------------+ 1 row in set (0.00 sec)Following is the query to search between comma separated values within one ... Read More
Let us first create a table −mysql> create table DemoTable -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> Name varchar(100), -> Age int -> ); Query OK, 0 rows affected (0.87 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(Name, Age) values('John', 21); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable(Name, Age) values('Carol', 22); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable(Name, Age) values('David', 23); Query OK, 1 row affected (0.54 sec)Display all records from the table using select statement ... Read More
To fetch rows where first character is not alphanumeric, you can use the following regular expression.Case 1 − If you want those rows that starts from a digit, you can use the following syntax −SELECT *FROM yourTableName WHERE yourColumnName REGEXP '^[0-9]';Case 2 − If you want those rows that start from an alphanumeric, use the following syntax −SELECT *FROM yourTableName WHERE yourColumnName REGEXP '^[^0-9A-Za-z]' ;To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table getRowsFirstNotAlphanumeric -> ( -> Id int NOT NULL AUTO_INCREMENT, -> UserPassword varchar(20), -> PRIMARY ... Read More
Yes, we can use ADD and CHANGE with ALTER statement. Let us first create a table −mysql> create table DemoTable -> ( -> Name varchar(100), -> Age int -> ); Query OK, 0 rows affected (0.84 sec)Now check the description of table.mysql> desc DemoTable;OutputThis will produce the following output −+-------+--------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------+--------------+------+-----+---------+-------+ | Name | varchar(100) | YES | | NULL | | | Age | int(11) ... Read More
For this, you can use UPDATE and concatenate the new data with the old one to save the old data as well −update yourTableName set yourColumnName=concat(yourColumnName, ", yourValue");Let us first create a table −mysql> create table DemoTable -> ( -> CustomerName varchar(100) -> ); Query OK, 0 rows affected (0.54 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris'); Query OK, 1 row affected (0.24 sec) mysql> insert into DemoTable values('David'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('Sam'); Query OK, 1 row affected (0.14 sec)Display all records from ... Read More
Let us first create a table −mysql> create table DemoTable -> ( -> Code varchar(100) -> ); Query OK, 0 rows affected (1.07 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('/101/102/106'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('/110/111/101'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('/111/114/201'); Query OK, 1 row affected (0.47 sec) mysql> insert into DemoTable values('/111/118'); Query OK, 1 row affected (0.13 sec)Display all records from the table using select statement −mysql> select *from DemoTable;OutputThis will produce ... Read More