Hypertechblog

DML Command Insert Command Its used to insert the record into table example- Command for inserting single record insert into <table name> values(value1, value2...) Command for inserting multiple command at a time insert into <table name> values(&col1, &col2...., &coln); whenever you enter query like this it will ask you to like this - enter a value for column1- value1.. and then hit enter  - enter a value for column2- value2.. and then hit enter - enter a value for column3- value3.. and then hit enter Now it will show 1 row created  if you want to create more record use / and hit enter SQL> /   hit enter // it will Execute most recent query again //this will so again and so on... - enter a value for column1- value1..  and then hit enter  - enter a value for column2- value2..  and then hit enter - enter a value for column3- value3..  and then hit enter // if you will miss any value here that will be inserted as NULL value Update command Used to upda

DDL Command CREATE Command It is used to create any data base object like tables, views, indexes, sequences, synonyms , users, functions, procedures, triggers, packages and so on. HOW TO CREATE A TABLE?            syn: CREATE TABLE <table_name>             (              <colname1> DATATYPE (size),               <colname2> DATATYPE (size),                : : : :,                : : : :,             ); INSERT Command This command is used for inserting new records into the tables          Syntax:           INSERT INTO <table_name>[(col1, col2,...., col n)]           VALUES(val1, val2,.....,val n);                  NOTE:  i) If number of columns in the table and number of values inserting in to the table      are equal, then no need to specify column names while inserting records.            ii) Char, Varchar2 and date type values should be enclosed in Single Quotes.            iii) If Number of inserting values are less than the

Naming Convention in SQL Rules to follow before specifying names(Object names, Column Names and Variable Names). Each name should begins alphabet Valid character set is a-z,A-Z,0-9,@,$,# and _ (underscore) Ex:  Emp123   Emp_o11 Names are not case sensitive Already existed names are not allowed Pre defined keywords (ReservedWords) are not allowed as names. Blankspace within a name is not allowed Max length of any name is 32 chars

Structured query language It is a collection of pre defined commands and constructs with syntactical rules. 1. Sql is a client tool to interact with ORACLE DB /any DB 2. Sql is to be installed in to the system whenever we have installed the db software. 3. Client [Technical] requests should be submitted in the form of "Queries". 4. Queries are executed by SQL STMT EXECUTOR ( Oracle Db Engine ) 5. Queries are executed against database and output will be displayed on the Sql * plus window.

If you are Getting any error in compiling main.js or app.js or in Entry file of React App You have to Update Babel versions and dependency npm install -D babel-loader @babel/core @babel/preset-env webpack And change config file options: {           presets: ['@babel/preset-env']         }

In java or other object oriented programming language is-a and has-a are two type of relationship under the concepts of inheritance. suppose we have three class Car. subaru. engine. subaru is a car — its a is-a  relationship  between  class  subaru and  class  car. car has a engine — its a has-a  relationship  between  class  car and  class  engine.

We can put the class name main their is no  compilation error or run time error . class main { public static void main(String []args) { // do your code } } now suppose our filename is ABC.java and now we are compiling it with command prompt- compiling- javac ABC.java Run- java main