#!/bin/bash

# Shows statistics for all indexes on all selected table

PORT=""
USER=""
TBL="%"
COLS=""

usage() {
    echo "Usage: $0 -d <dbname> [-U <user> -p <port> -t <table> -s ]"
    echo "dbname REQUIRED"
    echo "-s will show columns used in index"
    exit 1
}

getver()
{
VER=$(psql -t $PORT $USER $DBNAME <<_QRYVER_
SELECT version();
_QRYVER_
)
}

set_qry_cols() {

QRY="SELECT n.nspname as schema,
       i.relname as table,
       i.indexrelname as index,
       i.idx_scan,
       i.idx_tup_read,
       i.idx_tup_fetch,
       CASE WHEN idx.indisprimary
	    THEN 'pkey'
	    WHEN idx.indisunique
	    THEN 'uidx'
	    ELSE 'idx'
	    END AS type,
       pg_get_indexdef(idx.indexrelid, 1, FALSE) as idxcol1,
       pg_get_indexdef(idx.indexrelid, 2, FALSE) as idxcol2,
       pg_get_indexdef(idx.indexrelid, 3, FALSE) as idxcol3,
       pg_get_indexdef(idx.indexrelid, 4, FALSE) as idxcol4,
       CASE WHEN idx.indisvalid
	    THEN 'valid'
	    ELSE 'INVALID'
	    END as status,
       pg_relation_size( quote_ident(n.nspname) || '.' || quote_ident(i.relname) ) as size_in_bytes,
       pg_size_pretty(pg_relation_size(quote_ident(n.nspname)|| '.' || quote_ident(i.relname) )) as size
  FROM pg_stat_all_indexes i
  JOIN pg_class c ON (c.oid = i.relid)
  JOIN pg_namespace n ON (n.oid = c.relnamespace)
  JOIN pg_index idx ON (idx.indexrelid =  i.indexrelid )
 WHERE i.relname LIKE '%$TBL%'
   AND n.nspname NOT LIKE 'pg_%'
 ORDER BY 1, 2, 3;"

}

set_qry_nocols() {

QRY="SELECT n.nspname as schema,
       i.relname as table,
       i.indexrelname as index,
       i.idx_scan,
       i.idx_tup_read,
       i.idx_tup_fetch,
       CASE WHEN idx.indisprimary
	    THEN 'pkey'
	    WHEN idx.indisunique
	    THEN 'uidx'
	    ELSE 'idx'
	    END AS type,
       CASE WHEN idx.indisvalid
	    THEN 'valid'
	    ELSE 'INVALID'
	    END as status,
       pg_relation_size(quote_ident(n.nspname) || '.' || quote_ident(i.relname) ) as size_in_bytes
  FROM pg_stat_all_indexes i
  JOIN pg_class c ON (c.oid = i.relid)
  JOIN pg_namespace n ON (n.oid = c.relnamespace)
  JOIN pg_index idx ON (idx.indexrelid =  i.indexrelid )
 WHERE i.relname LIKE '%$TBL%'
   AND n.nspname NOT LIKE 'pg_%'
 ORDER BY 1, 2, 3;"

}

current_stats() {
STATLIST=$(psql -q -U postgres $DBNAME <<_QUERY_

$QRY

_QUERY_

)

}

###########################################################
#			 MAIN				  #
###########################################################

while getopts "d:p:st:uU:" OPT;
do case "${OPT}" in
      d) DBNAME=$OPTARG
	 ;;
      p) PORT="-p $OPTARG"
	 ;;
      s) COLS="TRUE"
	 ;;
      t) TBL="$OPTARG"
	 ;;
      U) USER="-U $OPTARG"
	 ;;
      u) usage
	 ;;
    [?]) usage
   esac;
done

if [ "$DBNAME" = "" ]
  then
    usage
fi

getver
VER=$(echo $VER | cut -c -16)
echo "Version is $VER"

if [ "$COLS" = "TRUE" ]
  then
    set_qry_cols
  else
    set_qry_nocols
fi

current_stats
echo "${STATLIST}"

exit 0