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The LM393 requires hysteresis, else the output could oscillate close to the switch over from day/nite.
Also how do you plan to set the lite/dark switch over for different environments/LDR's
The LM393 output is open collector, you need a pull up resistor to +v.
Add some decoupling caps across the power rails.
Wasting power with two 1k's across the supply, 10k's would be better.
I agree with 'ff',tidy up the polarity layout of the circuit