SQL Quick Reference...
SELECT field, field FROM table, table WHERE fieldname = value AND fieldname = value;
e.g.: select lastname, firstname from members where userid = 3;
ORDER BY field … sets up an ordering sequence
e.g.: select lastname, firstname from members where userid = 3 order by lastname;
Join two or more tables by setting shared fields...
e.g.: select * from members, progress where members.memid = progress.memid and members.lastname = ‘Smith’;
UPDATE table SET fieldname = value, fieldname = value WHERE fieldname = value;
e.g.: update members set lastname = ‘Smythe’ where lastname = ‘Smith’;
INSERT INTO tablename (fieldname, fieldname, …) VALUES (value, value, …);
e.g.: insert into exercises (activity, points) values (‘marathon running’, 1000);
DELETE fieldname, fieldname FROM table WHERE fieldname = value;
e.g.: delete * from progress where memid = 12;
Things to remember...
 | Always watch field types when constructing statements...
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| SQL statements are normally enclosed in double quotes when used in
programs...
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| Note that text fields are enclosed in single quotes...
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| In cases where a quote is included in the field, use a series of two
single quotes...
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| Dates are stored with a single quote and #, e.g., '#10/12/99#' | ||||||
| When constructing SQL statements, be very careful of where clauses, especially in update and delete statements. | ||||||
| Use dot notation in join table situations to identify which tables and fields...e.g., members.lastname | ||||||
| Test in the database application prior to running the query. | ||||||
| Logical operators include AND, OR, NOT | ||||||
| Algebra Operators: =, <> (not equal), > , < , Like (for comparisons) | ||||||
| Use the % for wild cards. |
