Let us first create a table −mysql> create table DemoTable    -> (    -> status int    -> ); Query OK, 0 rows affected (0.66 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(30); 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(20); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(30); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values(10); Query OK, 1 row affected (0.14 sec) ... Read More

Let us first create a table −mysql> create table DemoTable    -> (    -> Name varchar(100)    -> ); Query OK, 0 rows affected (1.32 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 (0.16 sec) mysql> insert into DemoTable values('DAVID'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('RObert'); Query OK, 1 row affected (0.21 sec)Display all records from the table using select statement −mysql> select *from DemoTable;Output+--------+ | Name ... Read More

The stripos() equivalent in MySQL is INSTR(), which returns the position of the first occurrence of a string in another string. Following is the syntax −select instr(yourColumnName, yourWord) As anyAliasName from yourTableName;Let us first create a table −mysql> create table DemoTable    -> (    -> Title text    -> ); Query OK, 0 rows affected (1.22 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('MySQL is my favourite subject'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('MongoDB is not my favourite subject'); Query OK, 1 row affected (0.20 sec)Display ... Read More

To remove seconds from MySQL datetime, use UPDATE and SET as in the following syntax −update yourTableName set yourDateColumnName=yourDateColumnName -second(yourDateColumnName);Let us first create a table −mysql> create table DemoTable    -> (    -> Shippingdatetime datetime    -> ); Query OK, 0 rows affected (0.76 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('2019-01-21 12:05:20'); Query OK, 1 row affected (0.25 sec) mysql> insert into DemoTable values('2019-03-01 10:23:35'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('2019-06-09 11:00:56'); Query OK, 1 row affected (0.14 sec)Display all records from the table ... Read More

Let us first create a table −mysql> create table DemoTable    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> Subject varchar(100)    -> ); Query OK, 0 rows affected (0.76 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(Subject) values('C'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable(Subject) values('MongoDB'); Query OK, 1 row affected (0.21 sec) mysql> insert into DemoTable(Subject) values('Java'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable(Subject) values('MongoDB'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable(Subject) ... Read More

To find the greatest value among four tables, you can use the method GREATEST(). Following is the query to create first table −mysql> create table DemoTable1    -> (    -> Value int    -> ); Query OK, 0 rows affected (0.70 sec)Insert some records in the first table using insert command −mysql> insert into DemoTable1 values(10); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable1 values(60); Query OK, 1 row affected (0.14 sec)Display all records from the first table using select statement −mysql> select *from DemoTable1;Output+-------+ | Value | +-------+ | 10 | ... Read More

For this, you can use SHOW COLUMNS command. Following is the syntax. Here, we have set the string using LIKE −SHOW COLUMNS FROM yourTableName LIKE ‘yourStringValue’;Let us first create a table −mysql> create table DemoTable    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> FirstName varchar(20),    -> LastName varchar(20)    -> ); Query OK, 0 rows affected (0.69 sec)Here is the query to select column names containing a specific string −mysql> SHOW COLUMNS FROM DemoTable LIKE 'FirstName';Output+-----------+-------------+------+-----+----------+-------+ | Field   | Type | Null | ... Read More

For this, you can use the DEFAULT CURRENT_TIMESTAMP clause in MySQL. Following is the syntax −CREATE TABLE yourTableName (    yourColumnName1 dataType1,    yourColumnName timestamp DEFAULT CURRENT_TIMESTAMP );Let us first create a table −mysql> create table DemoTable    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> DueDate timestamp default current_timestamp    -> ); Query OK, 0 rows affected (0.86 sec)Now you can insert some records in the table using insert command −mysql> insert into DemoTable values(); Query OK, 1 row affected (0.16 sec)Display all records from the table using select statement −mysql> select *from DemoTable;Output+----+---------------------+ ... Read More

To count number of elements in an array, use the aggregate framework. Let us first create a collection with documents −>db.countNumberOfElementsDemo.insertOne({"UserMessage":["Hi", "Hello", "Bye", "Awesome"]}); {    "acknowledged" : true,    "insertedId" : ObjectId("5cef8ec2ef71edecf6a1f6a1") }Display all documents from a collection with the help of find() method −> db.countNumberOfElementsDemo.find().pretty();This will produce the following output −{    "_id" : ObjectId("5cef8ec2ef71edecf6a1f6a1"),    "UserMessage" : [       "Hi",       "Hello",       "Bye",       "Awesome"    ] }Following is the query to count number of elements in an array −> db.countNumberOfElementsDemo.aggregate({$project: { NumberOfElements: { $size:"$UserMessage" }}})This will produce ... Read More

Let us first create a collection with documents −> db.queryMongoValueDemo.insertOne(    {       _id:101,       "ScoreDetails":[{Score:80}, {Score:45}, {Score:25}, {Score:70}]    } ); { "acknowledged" : true, "insertedId" : 101 } > db.queryMongoValueDemo.insertOne(    {       _id:102,       "ScoreDetails":[{Score:80}, {Score:24}, {Score:34}]    } ); { "acknowledged" : true, "insertedId" : 102 } > db.queryMongoValueDemo.insertOne(    {       _id:103,       "ScoreDetails":[{Score:99}, {Score:95}]    }   ); { "acknowledged" : true, "insertedId" : 103 }Display all documents from a collection with the help of find() method −> db.queryMongoValueDemo.find().pretty();This will produce the ... Read More