The file processing method is replaced by the data management system due to the data redundancy and data integrity. The data can be retrieved by the commands and structure queries which can be used on the specific records. It is easy to construct queries in the Access 2007 Access 2010 as it is designed to handle many kinds of operators. The unique symbol that activates the database is called an operator. The types of operators defined in Access 2007 Access 2010 are †relational operators, arithmetic operators, logical and special expressions like, is null, in , etc. . A structure query is formed by combining these operators. Greater than, greater than equal to, less than equal to and equal to are all comparison operators. As suggested from the name comparison operators are used to compare two values. These can be used under literal values, the values than can be directly entered into the records. Text, dates, numerals, time and constants are the literals known to the Access 2007 Access 2010. For example, you can compare the salaries of two employees using the comparison operators. Next are the arithmetic operators. They are the mathematical operators. The operators like sum, average, maximum, minimum, count, etc. are used as arithmetic operators. The main operations are modulus, addition, subtraction and multiplication/. One can use the sum operator to calculate the sum of the salaries of the employees working in a company. This is the easiest example. Also, count is used to count the number of records present in one column. We use 'like' operator to depict less important area. It is used with the wild cards like '?' or '*'. If you write like a*c, it will show all the words starting with 'a' and 'c' like acidic, amoebic, arithmetic, etc. The 'between .. and' is used to seek the range of values. The 'is null' is used to quest for the empty records. Logical operators are used to check the logic. Examples of logical operators are and, or, not, ex-or, nor, etc. their result is either true or false. For example, the 'and' operator gives the true value, if both the conditions are true. If any of the conditions is false, a false value is returned. Similarly, 'or' operator returns a true value, if only one of the conditions is true. 'Not' operator is used as the negation symbol. Ex-or stands for exclusive or. This structuring of queries becomes easier and quicker by using these operations.
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