Structured Query Language (SQL)

Lecture Notes Structured Query Language ❖ SQL is Structured Query Language, which is computer language for storing, manipulating and retrieving data stored in relational database. ❖ SQL is the standard language for relation database system. All relational database management systems like MySQL, MS Access, Oracle, Sybase, Informix, Postgres and SQL server use SQL as standard language database. Types of SQL Command ❑ Data definition language (DDL) ❑ Data manipulation language (DML) ❑ Data control language (DCL) ❑ Transaction control language (TCL) ❑ Data Query Language (DQL) SQL Data Types Date or Time Numeric o Bit o Tinyint o Smallint o In o Bigint o Decimal o Date o Time o Datetime o Timestamp o Year Unicode/Character/ String o Numeric o Nchar o Float o NVarchar o Real o Ntext o NVarchar (Max) Character or string o Char o Varchar o Text o Varchar (Max) Binary o Varbinary o Binary o Image o Varbinary (Max) Aggregate Function UPPER (): This function is used to convert all characters in a string to uppercase. Syntax: MAX (): This function returns the maximum values in a column. Syntax: LENGTH (): This function is t to return the length of a string. Syntax: CONTACT (): This Function is used to concatenate two or more strings together. Syntax: MIN (): This function returns the minimum value in a column. Syntax: COUNT (): This function returns the number of rows in a table or the number of non-null values in a column. Syntax: SUM (): This function returns the sum of all values in a column. Syntax: AVG (): This function returns the minimum value in a column. Syntax: GROUP BY (): This function is used to group the rows in a table based on the values in one or more columns and performs aggregate functions on each group. Syntax: MIN (): This function returns the minimum value in a column. Syntax: