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You can use INFORMATION_SCHEMA.COLUMNS to describe all tables in database through a single statement. The syntax is as follows.SELECT *FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA=’yourDatabaseName’\GHere I am using my database sample with two tables.The table names are as follows −mytableyourtableImplement the above syntax for your database. The query is as follows −mysql> select * FROM information_schema.columns WHERE table_schema = 'sample'\GThe following is the output describing the two tables in our database.*************************** 1. row *************************** TABLE_CATALOG: def TABLE_SCHEMA: sample TABLE_NAME: mytable COLUMN_NAME: id ORDINAL_POSITION: 1 COLUMN_DEFAULT: NULL IS_NULLABLE: YES DATA_TYPE: int CHARACTER_MAXIMUM_LENGTH: NULL CHARACTER_OCTET_LENGTH: NULL NUMERIC_PRECISION: 10 NUMERIC_SCALE: 0 DATETIME_PRECISION: NULL CHARACTER_SET_NAME: NULL ... Read More
To extract first word from a field, use in-built SUBSTRING_INDEX() function. The syntax is as follows −SELECT SUBSTRING_INDEX(yourColumnName, ’ ‘, 1) as anyVariableName from yourTableName;In the above query, if you use -1 in place of 1 then you will get the last word. To understand the above concept, let us create a table. The following is the query to create a table.mysql> create table FirstWordDemo −> ( −> AllWords longtext −> ); Query OK, 0 rows affected (0.83 sec)Now insert some words in the table using insert command. The query is ... Read More
In some cases, we should not allow application should run on rooted devices for payment gateways. This example demonstrates how to determine if running on a rooted device or not.Step 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. It contains information about root.Step 3 − Add the following code to src/MainActivity.javapackage com.example.andy.myapplication; import android.os.Build; import android.os.Bundle; import android.support.annotation.RequiresApi; import android.support.v7.app.AppCompatActivity; import android.widget.TextView; ... Read More
You need to use CASE statement to conditional select between dates to find the minimum and maximum price. Wrap up the CASE statement with aggregate function MIN() and MAX(). The syntax is as follows:SELECT MIN(CASE WHEN CURDATE() BETWEEN yourStartDateColumnName AND yourEndDateColumnName THEN yourLowPriceColumnName ELSE yourHighPriceColumnName END) AS anyVariableName, MAX(CASE WHEN CURDATE() BETWEEN yourStartDateColumnName AND yourEndDateColumnName THEN yourLowPriceColumnName ELSE yourHighPriceColumnName END) AS anyVariableName FROM yourTableName;To understand the above syntax, let us create a table. The query to create a table is as follows:mysql> create table ConditionalSelect -> ( -> Id int NOT NULL AUTO_INCREMENT, -> StartDate datetime, ... Read More
The Intel 8080 microprocessor was the predecessor of the 8085 or the Z-80 microprocessors. It was designed and manufactured by Intel. This Microprocessor was released on April 1974. It was an 8-bit Microprocessor.The Intel 8085 is also an 8-bit Microprocessor, which was introduced in 1976. It is very close to the 8080 microprocessor, but some slight changes and modifications are present. The Zilog Z-80 was also introduced in 1976. Basically, the Intel team was divided and formed a new Group called Zilog. The Zilog team was introduced the Z-80 Microprocessor.The 8080 MicroprocessorIn this diagram, we can see that the 8080 ... Read More
To remove the lowest element, use the pollFirst() method.Create a TreeSet and add elements to it −TreeSet tSet = new TreeSet(); tSet.add("78"); tSet.add("56"); tSet.add("88"); tSet.add("12");Now, remove the lowest element −tSet.pollFirst()The following is an example to remove lowest element in Java TreeSet −Example Live Demoimport java.util.*; public class Demo { public static void main(String args[]){ TreeSet tSet = new TreeSet(); tSet.add("78"); tSet.add("56"); tSet.add("88"); tSet.add("12"); ... Read More
This example demonstrates how to get Custom circle button in android.Step 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/actiivity_main.xml. In the above code, we have taken the button with a round_button background. so create round_button.xml in drawable folder and add the following code. ... Read More
All the classes in a package can be imported using the import statement along with the character *. For example - All the classes in the package java.util can be imported using import java.util.*;A program that demonstrates this in Java is given as follows:Example Live Demoimport java.util.*; public class Demo { public static void main(String args[]) { Stack stack = new Stack(); stack.push("Apple"); stack.push("Mango"); stack.push("Guava"); stack.push("Pear"); stack.push("Orange"); System.out.println("The stack elements are: " + stack); } }OutputThe stack elements ... Read More
In order to see the global locks in MySQL (Innodb), use the SHOW command. The below query shows the global locks as well owner of locks and waiters. The following query will also show transaction id and more related to Innodb.The query is as follows:mysql> SHOW ENGINE INNODB STATUS\GThe following is the output:*************************** 1. row *************************** Type: InnoDB Name: Status: ===================================== 2019-01-23 14:46:58 0x2914 INNODB MONITOR OUTPUT ===================================== Per second averages calculated from the last 23 seconds ----------------- BACKGROUND THREAD ----------------- srv_master_thread loops: 87 srv_active, 0 srv_shutdown, 51953 srv_idle srv_master_thread log flush and writes: 0 ---------- SEMAPHORES ---------- OS WAIT ... Read More
To get average on time column, use the below syntax. It will give the average in time format −SELECT SEC_TO_TIME(AVG(TIME_TO_SEC(yourColumnName))) as anyVariableName from yourTableName;To understand the above concept, let us create a table. The following is the query −mysql> create table AverageOnTime −> ( −> PunchInTime time −> ); Query OK, 0 rows affected (0.61 sec)Insert time values in the table using insert command. The query to insert records is as follows −mysql> insert into AverageOnTime values('00:00:40'); Query OK, 1 row affected (0.20 sec) mysql> insert into AverageOnTime values('00:02:50'); Query OK, 1 row affected (0.15 sec) ... Read More