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    Data Type  Description  Example  Operator                                 Description
     Stores date and time values in YYYY-MM- created_at TIMESTAMP;  <  Checks if the left value is less than the right value.
     TIMESTAMP
     DD HH:MM:SS format.  Example: ‘2025-07-10 14:30:00’
                                  >               Checks if the left value is greater than the right value.
     is_active BOOLEAN;
     BOOLEAN  Stores TRUE or FALSE values.  <=    Checks if the left value is less than or equal to the right value.
     Example: TRUE, FALSE
                                  >=              Checks if the left value is greater than or equal to the right value.

                     LOGICAL OPERATORS
     CHAR data type always takes the same space, while VARCHAR data type only uses space for    Logical operators are used to combine multiple conditions in a query. These operators allow
     the characters you type.
                     you to create complex queries. They include the following types:

                              Operator                                         Description

                      AND                         Returns TRUE if both conditions are true.
     SQL OPERATORS
                      OR                          Returns TRUE if at least one condition is true.
     SQL operators are used to perform operations on values in a SQL query. They enable access,   Reverses the  logical  state  of its  operand,  returning TRUE  if the

     comparison and modification of data in various ways.  NOT  condition is FALSE and vice versa.
     Some common types of operators in SQL are:

       Arithmetic operators     Comparison operators   SPECIAL OPERATORS
                     Some special operators in SQL are as follows:
       Logical operators      Special operators
                              Operator                                         Description
     ARITHMETIC OPERATORS
                      ALL                         Returns TRUE if all of the subquery values meet the condition.
     Arithmetic operators perform basic mathematical operations on numerical data. They include
     the following types:  ANY                    Returns TRUE if any of the subquery values meet the condition.
                                                  Used to indicate a range which otherwise is done using relational
     Operator  Description  BETWEEN
                                                  operators.
     + (Addition)  Adds two values.
                      EXISTS                      Returns TRUE if the subquery returns one or more records.
     - (Subtraction)  Subtracts one value from another.

     * (Multiplication)  Multiplies two values.
     / (Division)  Divides one value by another.
                            SQL CONSTRAINTS
     % (Modulus)  Returns the remainder when one value is divided by another.
                     SQL  constraints are used  to  define  rules for table  data.  These rules control  the  data  that
     COMPARISON OPERATORS  can be stored in a column. Constraints are used to restrict the types of data that can be entered
     Comparison operators are used to compare two expressions or values. They help in filtering   into a table.

     data based on conditions. They include the following types:  Some different types of constraints include:
     Operator  Description    NULL constraint: The NULL constraint allows a column to store NULL values. If no value is

     =  Checks if two values are equal.  provided during insert or update, it does not cause an error.

     != or <>  Checks if two values are not equal.    NOT NULL constraint: The NOT NULL constraint specifies that a column must have a value.
                        Records cannot be inserted or updated without providing a value for this column.

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                                                                                              MySQL: My First Database

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