MySQL/Tutorials

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Revision as of 13:51, 5 March 2008 by imported>Eric Evers (→‎Queries)
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MySQL tutorial

Intall

Create User

Create Database

Queries

Sub Quries

Aggragate Functions

String functions

Pattern Matching

Using Like
Using RegExp

Regular expressions in SQL

Lets create a simple table.

CREATE TABLE word (name varchar(20));
INSERT into word VALUES ("people"),("places"),("things"),("ppl");
SELECT * FROM word;
+--------+
| name   | 
+--------+
| people |
| places |
| things |
| ppl    |
+--------+

Look for two p's in a row.

SELECT * FROM word WHERE name RegExp "[p]{2}" 
+--------+
| name   | 
+--------+
| ppl    |
+--------+

A "." is any character. A "+" is one or more copies of a character. A "C{n}" looks for n copies of C. Look for two p's but not next to one another.

SELECT * FROM word WHERE name RegExp "p.+p" 
+--------+
| name   | 
+--------+
| people |
+--------+
Exercises

Give a sql regular expression query that will select:

1) only things  
2) only ppl and places
3) only people and places
4) only things and places