SQL Tuning

Colophon

Our look is the result of reader comments, our own experimentation, and feedback from distribution channels. Distinctive covers complement our distinctive approach to technical topics, breathing personality and life into potentially dry subjects.

The animal on the cover of SQL Tuning is a salamander. Though mature salamanders bear a superficial resemblance to small lizards, salamanders are not reptiles; rather, they are amphibians that retain their tails as adults. Like all amphibians, a salamander begins life underwater as a gelatinous egg and develops through a series of stages. Newly hatched salamander larvae resemble tadpoles (the larval form of toads and frogs) and breathe through gills. As they mature, salamanders develop legs and lungs, which allow them to leave the water and breathe air. But they remain in or around streams, rivers, ponds, lakes, or moist woodlands throughout their lives. They must return to a freshwater source to lay their eggs.

The most immediately recognizable difference between adult salamanders and lizards is the former’s lack of scales; a salamander’s skin is smooth and porous and is used to absorb moisture. Salamanders’ skin can be any of a variety of colors - from brown or black to yellow or red - and is often covered with dark spots, bars, or stripes. As they grow, salamanders molt their skin, usually every few days or every few weeks. Salamanders also have the ability to shed and regrow their tails and other parts of their body that become ...