Error happen when Compile C program

[root(at)DA primary_db_la]# make clean;make
rm --force run_db
rm --force *.bak
rm --force *.orig
gcc -L /usr/lib -lpq -o run_db \
primary_db_main.o primary_db_start.o primary_db_init.o
business_data_analysis.o \
shmsem.o primary_db_monitor_process.o primary_db_sync.o
primary_db_watch_dog.o \
primary_db_comm_proxy.o primary_db_comm_database.o primary_db_heart_beat.o
\
check.o ctl_channel.o longlink.o config.o parse_pkt_common.o \
parse_pkt_common_header.o primary_db_record.o primary_db_view.o \
multi_recvsend.o primary_db_cas.o
/usr/bin/ld: cannot find -lpq
collect2: ld

how can i make the program? please help.