tailieunhanh - Mysql your visual blueprint for creating open source databases- P9

Mysql your visual blueprint for creating open source databases- P9:The show tables command displays a list of tables available in the currently selected database. You can use this command when you are unsure of the exact name of a table within the database. | USING MYSQL FUNCTIONS 7 MySQL also includes functions that allow you to search a string for a particular substring. The first of these LOCATE searches a text value for a string you specify. If the string is found within the larger string it returns a number indicating the character position where it starts. If the string is not found LOCATE returns zero. The following query searches the values of the quote column in the quotes table for the string every and displays the results Example SELECT LOCATE every quote FROM quotes The LOCATE function also accepts a third optional parameter. If you specify a number after the two strings MySQL will only search for the substring starting with the character index you specify. This is useful when you want to find the second or third occurrence of a string. MySQL also supports the INSTR function for compatibility with other database systems. This function is similar to LOCATE but the parameters are in the opposite order you first specify the larger string and then the substring to search for. Unlike LOCATE INSTR does not support a starting position for the search. -Q Type SELECT author RIGHT quote 10 and press Enter. O Type FROM quotes and press Enter. -0 Type SELECT author MID quote 5 10 and press Enter. L H Type FROM quotes and press Enter. This displays the author column and the last ten characters of the quote column for each row. Th is displays the author column and ten characters of the quote column starting at the fifth character. 147 MySQL UNDERSTANDING DATE AND TIME FUNCTIONS MySQL allows you to store a date or date time combination in several column types including DATE TIME DATETIME and TIMESTAMP. MySQL also includes a number of functions that allow you to work with dates and times and convert them into different formats. GET THE CURRENT DATE If you need to know the current date within a MySQL query you can use the NOW function. This function returns the current date and time. If you use this function as a string .