Articles on Trending Technologies

Technical articles with clear explanations and examples

How to use in android CopyOnWriteArraySet?

karthikeya Boyini
karthikeya Boyini
Updated on 30-Jun-2020 246 Views

Before getting into an example, we should know what CopyOnWriteArraySet is. It is a thread-safe variant of ArrayList and operations add, set, and so on by making a fresh copy of the underlying array.This example demonstrates about How to use in android CopyOnWriteArraySetStep 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 − Add the following code to res/layout/activity_main.xml.     In the above code, we have taken a text view to show CopyOnWriteArraySet elements.Step 3 − Add the following code to ...

Read More

Given a column name how can I find which tables in a MySQL database contain that column?

karthikeya Boyini
karthikeya Boyini
Updated on 30-Jun-2020 232 Views

Use the COLUMN_NAME to find which table in a database contains a specific column. Let us first create a table −mysql> create table DemoTable    -> (    -> CustomerId int,    -> CustomerName varchar(20),    -> CustomerCountryName varchar(100)    -> ); Query OK, 0 rows affected (1.05 sec)Following is the query to find in which tables a specific column “'CustomerCountryName'” is present −mysql> select *from information_schema.columns WHERE COLUMN_NAME = 'CustomerCountryName';OutputThis will produce the following output −+---------------+--------------+--------------+---------------------+------------------+----------------+-------------+-----------+--------------------------+------------------------+-------------------+---------------+--------------------+--------------------+-----------------+--------------+------------+-------+---------------------------------+----------------+-----------------------+-------+ | TABLE_CATALOG | TABLE_SCHEMA | TABLE_NAME  | COLUMN_NAME          |ORDINAL_POSITION  | COLUMN_DEFAULT | IS_NULLABLE | DATA_TYPE |CHARACTER_MAXIMUM_LENGTH | CHARACTER_OCTET_LENGTH |NUMERIC_PRECISION ...

Read More

How to use CopyOnWriteArrayList in android?

Samual Sam
Samual Sam
Updated on 30-Jun-2020 346 Views

Before getting into an example, we should know what CopyOnWriteArrayList is. It is a thread-safe variant of ArrayList and operations add, set, and so on by making a fresh copy of the underlying array.This example demonstrates about How to use CopyOnWriteArrayList in androidStep 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 − Add the following code to res/layout/activity_main.xml.     In the above code, we have taken a text view to show CopyOnWriteArrayList elements.Step 3 − Add the following code to ...

Read More

How to order MySQL rows by multiple columns?

karthikeya Boyini
karthikeya Boyini
Updated on 30-Jun-2020 344 Views

Let us first create a table −mysql> create table DemoTable    -> (    -> FirstName varchar(20),    -> LastName varchar(20)    -> ); Query OK, 0 rows affected (1.44 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John', 'Smith'); Query OK, 1 row affected (0.35 sec) mysql> insert into DemoTable values('Chris', 'Brown'); Query OK, 1 row affected (0.37 sec) mysql> insert into DemoTable values('Carol', 'Taylor'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('David', 'Miller'); Query OK, 1 row affected (0.24 sec)Display all records from the table using ...

Read More

How to use containsAll() in android CopyOnWriteArraySet?

karthikeya Boyini
karthikeya Boyini
Updated on 30-Jun-2020 227 Views

Before getting into an example, we should know what CopyOnWriteArraySet is. It is a thread-safe variant of ArrayList and operations add, set, and so on by making a fresh copy of the underlying array.This example demonstrates about How to use containsAll() in android CopyOnWriteArraySetStep 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 − Add the following code to res/layout/activity_main.xml.     In the above code, we have taken a text view to show CopyOnWriteArraySet elements.Step 3 − Add the following code ...

Read More

Sort a column ignoring a specific word in MySQL

karthikeya Boyini
karthikeya Boyini
Updated on 30-Jun-2020 221 Views

Let us first create a table −mysql> create table DemoTable    -> (    -> Name text    -> ); Query OK, 0 rows affected (1.31 sec)Insert some records in the table using insert command. Here, we have inserted a name with a specific word “name”, which we need to ignore −mysql> insert into DemoTable values('John 7'); Query OK, 1 row affected (0.65 sec) mysql> insert into DemoTable values('John 6'); Query OK, 1 row affected (0.42 sec) mysql> insert into DemoTable values('John 9'); Query OK, 1 row affected (0.33 sec) mysql> insert into DemoTable values('name John 3'); ...

Read More

How to use contains() in android PriorityBlockingQueue?

Samual Sam
Samual Sam
Updated on 30-Jun-2020 174 Views

Before getting into an example, we should know what PriorityBlockingQueue is. It is an unbounded queue and follows the same order as a priority queue. The main usage of priority blocking queue is, it going to handle out of memory error.This example dem   onstrates about How to use contains() in android PriorityBlockingQueueStep 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 − Add the following code to res/layout/activity_main.xml.     In the above code, we have taken a text view to ...

Read More

How to search a MySQL table for a specific string?

Sharon Christine
Sharon Christine
Updated on 30-Jun-2020 2K+ Views

Use equal to operator for an exact match −select *from yourTableName where yourColumnName=yourValue;Let us first create a table −mysql> create table DemoTable -> ( -> FirstName varchar(100), -> LastName varchar(100) -> ); Query OK, 0 rows affected (0.70 secInsert some records in the table using insert command −mysql> insert into DemoTable values('John', 'Smith'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('John', 'Doe'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('Chris', 'Brown'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('Carol', 'Taylor'); Query OK, 1 row affected ...

Read More

How to update multiple rows and left pad values in MySQL?

Sharon Christine
Sharon Christine
Updated on 30-Jun-2020 491 Views

Use the LPAD() function to left pad values. Let us first create a table −mysql> create table DemoTable    -> (    -> Number int    -> ); Query OK, 0 rows affected (2.26 secInsert some records in the table using insert command −mysql> insert into DemoTable values(857786); Query OK, 1 row affected (0.26 sec) mysql> insert into DemoTable values(89696); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values(89049443); Query OK, 1 row affected (0.25 secDisplay all records from the table using select statement −mysql> select *from DemoTable;OutputThis will produce the following output −+----------+ | ...

Read More

Change the column name from StudentName to FirstName in MySQL?

karthikeya Boyini
karthikeya Boyini
Updated on 30-Jun-2020 243 Views

Use CHANGE with ALTER statement. Let us first create a table −mysql> create table DemoTable -> ( -> StudentName 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 | +----------------+--------------+------+-----+---------+-------+ | StudentName    | varchar(100) | YES | | NULL | | | Age         ...

Read More
Showing 52591–52600 of 61,297 articles
Advertisements