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Transcript of Foreign Language Specialized
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8/3/2019 Foreign Language Specialized
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Foreign
Language
Specia
lizedLecturer:
Student
:1.Ngo
Vu
Linh
2. LeVa
nLinh
aTanDat
4.Tra
nQuan
gNhu
5. DangV
anHoai
6.VoN
gocThu
Mr.Duyet
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SQL is a standard language for accessing
and manipulating databases.
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What isSQL?
SQL stands for Structured QueryLanguage
SQL lets you access and manipulate
databases SQL is an ANSI (American National
Standards Institute) standard
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What Can SQLdo?
SQL can execute queries against a database
SQL can retrieve data from a database SQL can insert records in a database SQL can update records in a database SQL can delete records from a database
SQL can create new databases SQL can create new tables in a database SQL can create stored procedures in a database SQL can create views in a database SQL can set permissions on tables, procedures,
and viewsq SQL can be divided into two parts: The Data
Manipulation Language (DML) and the Data
Definition Language (DDL).
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q The query and update commands
form the DML part of SQL:
SELECT- extracts data from a database
UPDATE - updates data in a database
DELETE - deletes data from a database
INSERT INTO - inserts new data into a
database
What Can SQLdo?
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q The DDL part of SQL permits database
tables to be created or deleted. It alsodefines indexes (keys), specifies linksbetween tables, and imposes constraintsbetween tables. The most important DDL
statements in SQL are:
What Can SQLdo?
CREATE DATABASE - creates a new database ALTER DATABASE - modifies a database CREATE TABLE - creates a new table
ALTER TABLE - modifies a table DROP TABLE - deletes a table CREATE INDEX- creates an index (search
key) DROP INDEX- deletes an index
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The SQL SELECT Stateme
q
The SELECT statement is used to select data from adatabase.
q The result is stored in a result table, called the
result-set
SQL SELECT Syntax
SELECT column_name(s)FROM table_name
and
SELECT * FROM table_name
Note: SQL is not case sensitive. SELECT is the sameas select.
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An SQL SELECTExample
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SELECT * Exampl
q Now we want to select all the columns from the
"Persons" table.q We use the following SELECT statement:
SELECT * FROM Persons
Tip: The asterisk (*) is a quick way of selecting allcolumns!
q The result-set will look like this:
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Navigation in aResult-set
q Most database software systems allow navigation inthe result-set with programming functions, like:Move-To-First-Record, Get-Record-Content, Move-To-Next-Record, etc.
q Programming functions like these are not a part ofthis tutorial. To learn about accessing data withfunction calls, please visit ourADO tutorial or ourPHP tutorial.
http://w3schools.com/ado/default.asphttp://w3schools.com/php/default.asphttp://w3schools.com/php/default.asphttp://w3schools.com/ado/default.asp -
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The INSERT INTO Stateme
q The INSERT INTO statement is used toinsert a new row in a table.
q The INSERT INTO statement is used toinsert new records in a table.
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SQL INSERT INTO Synt
q It is possible to write the INSERT INTO statementin two forms.
q The first form doesn't specify the column names
where the data will be inserted, only their values:q INSERT INTO table_name
VALUES (value1, value2, value3,...)q The second form specifies both the column names
and the values to be inserted:q INSERT INTO table_name (column1, column2,
column3,...)VALUES (value1, value2, value3,...)
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SQL INSERT INTO Examp
We have the following "Persons" table:
q Now we want to insert a new row in the"Persons" table.
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q We use the following SQL statement:
INSERT INTO PersonsVALUES (4,'Nilsen', 'Johan', 'Bakken 2','Stavanger')
q The "Persons" table will now look like this:
SQL INSERT INTO Examp
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Insert Data Only in Specified Colu
q It is also possible to only add data in specific
columns.q The following SQL statement will add a new row,
but only add data in the "P_Id", "LastName" and
the "FirstName" columns:q INSERT INTO Persons (P_Id, LastName, FirstName)
VALUES (5, 'Tjessem', 'Jakob')
The "Persons" table will now look like this:
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The CREATE TABLE Stateme
q
The CREATE TABLE statement is used to create atable in a database.SQL CREATE TABLE SyntaxCREATE TABLE table_name(
column_name1 data_type,column_name2 data_type,column_name3 data_type,....
)q The data type specifies what type of data thecolumn can hold. For a complete reference of allthe data types available in MS Access, MySQL,and SQL Server, go to our complete
Data Types reference.
C
http://w3schools.com/sql/sql_datatypes.asphttp://w3schools.com/sql/sql_datatypes.asp -
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CREATE TABLE Examp
q Now we want to create a table called "Persons"
that contains five columns: P_Id, LastName,
FirstName, Address, and City.
q We use the following CREATE TABLE statement:
q CREATE TABLE Persons
(
P_Id int,
LastName varchar(255),
FirstName varchar(255),
Address varchar(255),
City varchar(255)
CREATE TABLE E
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q The P_Id column is of type int and will hold a
number. The LastName, FirstName, Address, and
City columns are of type varchar with a maximum
length of 255 characters.
q The empty "Persons" table will now look like this:
q The empty table can be filled with data with the
INSERT INTO statement.
CREATE TABLE Examp
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Thank You !