当然了对于不同的表来说，应该还是可以做一些细分，能够最大程度的提高效率，比如表中含有主键列，尝试走索引扫面可能会被全表扫描效率要高。如果表中的数据太多，而且没有一些相关的约束，可以考虑使用并行来提高等等。
以下就是使用shell脚本所做的查询数据条数的一个例子，看起来有些太不值得了，但是如果数据量很大的情况下这些分析就格外有用了。
比如表customer，数据量不是很大，可以直接走索引来做。
> ksh get_tab_cnt.sh prdappo customer
************************************************
CUSTOMER .859375
CUSTOMER
select /*+ index_ffs(CUSTOMER,CUSTOMER_pk ) parallel_index(CUSTOMER,CUSTOMER_pk,1) */ 'CUSTOMER,', count(*) from CUSTOMER ;
************************************************
GREEMENT 10.359375
GREEMENT
select /*+ index_ffs(GREEMENT,GREEMENT_pk ) parallel_index(GREEMENT,GREEMENT_pk,4) */ 'GREEMENT,', count(*) from GREEMENT ;
对应的脚本如下：
#!/bin/ksh
#get_tab_cnt_sql
DATE=`/bin/date '+%y%m%d_%H%M%S'`
constr1=$DB_CONN_STR@$SH_DB_SID
constr1=`echo ${constr1} | tr '[:lower:]' '[:upper:]'`
timestamp=$3
time_vs=""
if [ "${timestamp}" = "" ]
then
echo " "
echo " "
else
if [ "${timestamp2}" = "" ]
then
exit;
else
time_vs=" As of timestamp to_date('${timestamp}','mm/dd/yyyy hh24:mi:ss') "
time_vt=" As of timestamp to_date('${timestamp2}','mm/dd/yyyy hh24:mi:ss') "
fi
fi
user1=`echo $constr1 | awk -F "/" '{print $1}'`
inst1=`echo $constr1 | awk -F "@" '{print $2}'`
if [[ -z ${inst1} ]];then
inst1=$ORACLE_SID
constr1=${constr1}@${inst1}
fi
function check_connectivity
{
Num=`echo show user | $ORACLE_HOME/bin/sqlplus -s $1| grep -i 'USER ' | wc -l`
if [ $Num -gt 0 ]
then
## ok - instance is accessible
echo '************************************************'
else
## inst is Inaccessible
echo Connection Details: `echo $1 ` is Inaccessible...
echo '************************************************'
exit;
fi
}
check_connectivity $constr1
sleep 1;
sleep 1;
mkdir `pwd`/Get_tab_cnt_${user1}_${inst1}_${DATE}
mkdir `pwd`/Get_tab_cnt_${user1}_${inst1}_${DATE}/List
small2='1'
small='10'
medium='30'
big_par=8
medium_par=4
small_par=2
small2_par=1
COUNT_DIR=`pwd`/Get_tab_cnt_${user1}_${inst1}_${DATE}
exclude_tab=x
sqlplus -s ${constr1}
set head off
set line 100
set pages 50000
set long 10000
col segment_name for a40
spool ${COUNT_DIR}/List/${user1}_${inst1}_all_tab_size_temp.lst
select distinct segment_name,to_number(to_char(sum(bytes/1024/1024/1024))) from dba_segments
where owner=upper('$1') and segment_name =upper('$2') group by segment_name order by 2 desc;
spool off;
spool ${COUNT_DIR}/List/${user1}_${inst1}_all_tab_with_pk.lst
select table_name from dba_tables where owner=upper('$1') and table_name in ( select table_name from dba_constraints where owner=upper('$1') and table_name =upper('$2')
and constraint_type='P');
spool off;
EOF
################## Getting Big Tables ######################
sed '/^$/d' ${COUNT_DIR}/List/${user1}_${inst1}_all_tab_size_temp.lst | grep -v SQL | grep -v select | grep -v ERROR | grep -v ORA- | grep -v '*' > ${COUNT_DIR}/List/${user1}_${inst1}_all_tab_size.lst
echo ${medium} | awk -v medium=${medium} ' $2 > medium { print $1 } ' ${COUNT_DIR}/List/${user1}_${inst1}_all_tab_size.lst > ${COUNT_DIR}/List/${user1}_${inst1}_big_tab.lst
echo ${medium} | echo ${small} | awk -v medium=${medium} -v small=${small} ' $2 small { print $1 } ' ${COUNT_DIR}/List/${user1}_${inst1}_all_tab_size.lst > ${COUNT_DIR}/List/${user1}_${inst1}_medium_tab.lst
echo ${small} | echo ${small2} | awk -v small=${small} -v small2=${small2} ' $2 small2 { print $1 } ' ${COUNT_DIR}/List/${user1}_${inst1}_all_tab_size.lst > ${COUNT_DIR}/List/${user1}_${inst1}_small_tab.lst
echo ${small2} | awk -v small2=${small2} ' $2 ${COUNT_DIR}/List/${user1}_${inst1}_small2_tab.lst
###############################( Generating Count Files ( Big ) #############################################
while read table
do
is_pk=`grep -i ${table} ${COUNT_DIR}/List/${user1}_${inst1}_all_tab_with_pk.lst | wc -l `
is_pk=`echo $is_pk`
if [ is_pk -ne 0 ]
then
echo "select /*+ index_ffs(${table},${table}_pk ) parallel_index(${table},${table}_pk,${big_par}) */ '${table},', count(*) from ${table} ${time_vs} ;" >> ${COUNT_DIR}/sqls/${user1}_${inst1}_${table}_tab_count.sql
else
echo "select /*+ PARALLEL(${table},${big_par}) */ '${table} ,' , count (1) from ${table} ${time_vs} ;" >> ${COUNT_DIR}/sqls/${user1}_${inst1}_${table}_tab_count.sql
fi
done
################################ Generating Count Files ( Medium ) #############################################
while read table
do
#echo " Table Name is : $table "
is_pk=`grep -i ${table} ${COUNT_DIR}/List/${user1}_${inst1}_all_tab_with_pk.lst | wc -l `
is_pk=`echo $is_pk`
if [ is_pk -ne 0 ]
then
echo "select /*+ index_ffs(${table},${table}_pk ) parallel_index(${table},${table}_pk,${medium_par}) */ '${table},', count(*) from ${table} ${time_vt} ;" >> ${COUNT_DIR}/List/${user1}_${inst1}_medium_tab_count.lst
else
echo "select /*+ PARALLEL(${table},${medium_par}) */ '${table} ,' , count (1) from ${table} ${time_vs} ;" >> ${COUNT_DIR}/List/${user1}_${inst1}_medium_tab_count.lst
fi
done
################################ Generating Count Files ( Small ) #############################################
while read table
do
#echo " Table Name is : $table "
is_pk=`grep -i ${table} ${COUNT_DIR}/List/${user1}_${inst1}_all_tab_with_pk.lst | wc -l `
is_pk=`echo $is_pk`
if [ is_pk -ne 0 ]
then
echo "select /*+ index_ffs(${table},${table}_pk ) parallel_index(${table},${table}_pk,${small_par}) */ '${table},', count(*) from ${table} ${time_vs} ;" >> ${COUNT_DIR}/List/${user1}_${inst1}_small_tab_count.lst
else
echo "select /*+ PARALLEL(${table},${small_par}) */ '${table} ,' , count (1) from ${table} ${time_vs} ;" >> ${COUNT_DIR}/List/${user1}_${inst1}_small_tab_count.lst
fi
done
################################ Generating Count Files (Very Small ) #############################################
while read table
do
#echo " Table Name is : $table "
is_pk=`grep -i ${table} ${COUNT_DIR}/List/${user1}_${inst1}_all_tab_with_pk.lst | wc -l `
is_pk=`echo $is_pk`
if [ is_pk -ne 0 ]
then
echo "select /*+ index_ffs(${table},${table}_pk ) parallel_index(${table},${table}_pk,${small2_par}) */ '${table},', count(*) from ${table} ${time_vs} ;" >> ${COUNT_DIR}/List/${user1}_${inst1}_small2_tab_count.lst
else
echo "select /*+ PARALLEL(${table},${small2_par}) */ '${table} ,' , count (1) from ${table} ${time_vs} ;" >> ${COUNT_DIR}/List/${user1}_${inst1}_small2_tab_count.lst
fi
done
rm ${COUNT_DIR}/List/*temp.lst
#################### get table list from schemas ##########################
touch ${COUNT_DIR}/${user1}_${inst1}_final_tab_cnt_stats.sql
schema_con=${user1}_${inst1}
function get_final_tab_cnt_stats
{
schema_type=$1
if [ -s ${COUNT_DIR}/List/${schema_con}_big_tab_count.lst ];then
cat ${COUNT_DIR}/List/${schema_con}_big_tab_count.lst >> ${COUNT_DIR}/${schema_con}_final_tab_cnt_stats.sql
fi
if [ -s ${COUNT_DIR}/List/${schema_con}_medium_tab_count.lst ];then
cat ${COUNT_DIR}/List/${schema_con}_medium_tab_count.lst >> ${COUNT_DIR}/${schema_con}_final_tab_cnt_stats.sql
fi
if [ -s ${COUNT_DIR}/List/${schema_con}_small2_tab_count.lst ];then
cat ${COUNT_DIR}/List/${schema_con}_small2_tab_count.lst >> ${COUNT_DIR}/${schema_con}_final_tab_cnt_stats.sql
fi
if [ -s ${COUNT_DIR}/List/${schema_con}_small_tab_count.lst ];then
cat ${COUNT_DIR}/List/${schema_con}_small_tab_count.lst >> ${COUNT_DIR}/${schema_con}_final_tab_cnt_stats.sql
fi
}
get_final_tab_cnt_stats $schema_con
cat ${COUNT_DIR}/${schema_con}_final_tab_cnt_stats.sql
rm -rf ${COUNT_DIR}