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Found 6705 Articles for Database

433 Views
Use COUNT() function along with GROUP BY clause for this. Let us first create a table −mysql> create table DemoTable -> ( -> Name varchar(100) -> ); Query OK, 0 rows affected (0.69 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('Sam'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('John'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('Mike'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('John'); Query ... Read More

328 Views
For this, use CASE statement. This will work even without using temporary tables. Let us first create a table −mysql> create table DemoTable -> ( -> UserName varchar(100), -> UserStatus varchar(100) -> ); Query OK, 0 rows affected (0.74 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John', 'Active'); Query OK, 1 row affected (0.29 sec) mysql> insert into DemoTable values('Chris', 'Inactive'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('Bob', 'Inactive'); Query OK, 1 row affected (0.32 sec) mysql> insert into DemoTable values('Robert', 'Active'); ... Read More

1K+ Views
Let us first create a table −mysql> create table DemoTable -> ( -> AdmissionDate date -> ); Query OK, 0 rows affected (1.38 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('2019-05-12'); Query OK, 1 row affected (0.52 sec) mysql> insert into DemoTable values('2019-05-18'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('2019-04-19'); Query OK, 1 row affected (0.42 sec)Display all records from the table using select statement −mysql> select *from DemoTable;OutputThis will produce the following output −+---------------+ | AdmissionDate | +---------------+ | 2019-05-12 | | 2019-05-18 ... Read More

98 Views
Use zerofill for this in MySQL. Zerofill pads the displayed value of the field with zeros up to the display width specified in the column definition. For example, if column is set int(8), therefore the width is 8. If the number is let’s say 29654, then zero will be padded on the left for total width i.e.8 −00029654Let us first create a table −mysql> create table DemoTable -> ( -> Number int(8) zerofill -> ); Query OK, 0 rows affected (0.50 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(10); Query OK, 1 row affected ... Read More

112 Views
To fetch a single date from a column, use “LIMIT 1. To order it, use ORDER BY clause. Let us first create a table −mysql> create table DemoTable -> ( -> DueDate varchar(100) -> ); Query OK, 0 rows affected (1.16 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('10-06-2019'); Query OK, 1 row affected (0.42 sec) mysql> insert into DemoTable values('01-12-2016'); Query OK, 1 row affected (0.52 sec) mysql> insert into DemoTable values('31-01-2018'); Query OK, 1 row affected (0.58 sec)Display all records from the table using select statement −mysql> select *from DemoTable;OutputThis ... Read More

303 Views
Let us first create a table −mysql> create table DemoTable -> ( -> Words text -> ); Query OK, 0 rows affected (0.54 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Ever'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable values('Forever'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('Good'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('Never'); Query OK, 1 row affected (0.12 sec)Display all records from the table using select statement −mysql> select *from DemoTable;Output+---------+ | Words ... Read More

119 Views
We will first order by DESC and then fetch the value associated with maximum id −select *from yourTableName order by yourColumnName DESC LIMIT 1, 1;Let us first create a table −mysql> create table DemoTable -> ( -> Alldata int -> ); Query OK, 0 rows affected (0.63 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(303); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable values(560); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(100); Query OK, 1 row affected (0.13 sec) mysql> insert ... Read More

223 Views
Let us first create a table −mysql> create table DemoTable -> ( -> Name varchar(100), -> Code 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', '0001'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('Robert', '0002'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values('Robert', '0003'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('Chris', '0001'); Query OK, 1 row affected (0.12 sec)Display all records from the table using ... Read More

908 Views
Let us first create a table −mysql> create table DemoTable -> ( -> Amount int -> ); Query OK, 0 rows affected (0.50 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 (0.11 sec) mysql> insert into DemoTable values(30); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values(40); Query OK, 1 row affected (0.15 sec)Display all records from the table using select statement −mysql> select *from DemoTable;Output+--------+ | Amount ... Read More

20K+ Views
To delete all rows older than 30 days, you need to use the DELETE with INTERVAL. Use < now() i.e. less than operator to get all the records before the current date.Let us first create a table −mysql> create table DemoTable -> ( -> UserMessage text, -> UserMessageSentDate date -> ); Query OK, 0 rows affected (0.59 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Hi', '2019-06-01'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('Hello', '2019-07-02'); Query OK, 1 row affected (0.14 sec) mysql> insert ... Read More