Overview#Although Comparing LDAP and SQL is a common discussion, it is really comparing Apples and Oranges.
LDAP is a Communications protocol and SQL (Structured Query Language) is a special-purpose programming language designed for managing data in relational database management systems (RDBMS).
A Communications protocol defines the syntax, semantics, and synchronization of communication; the specified behavior is typically independent of how it is to be implemented.
Servers and Clients#Any LDAP Client, like LDAP Browsers, can communicate with any LDAP Server Implementation. This is not the same in SQL where each SQL Client must use a specific protocol for each SAL Server implementation.
More Information#There might be more information for this subject on one of the following:
[#1] - http://en.wikipedia.org/wiki/Communications_protocol retrieved 2013-01-03