#!/bin/sh
# -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- #
# Package : reindexdb                 Version : $Revision: 1.6 $
# Date    : 05/08/2002                Author  : Shaun Thomas
# Req     : psql, sh, perl, sed         Type  : Utility
#
# -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- #

# -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- #
# Function Definitions
# -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- #

usage()
{
  echo "$CMDNAME reindexes a PostgreSQL database."
  echo
  echo "Usage:"
  echo "  $CMDNAME [options] [dbname]"
  echo
  echo "Options:"
  echo "  -h, --host=HOSTNAME             Database server host"
  echo "  -p, --port=PORT                 Database server port"
  echo "  -U, --username=USERNAME         Username to connect as"
  echo "  -W, --password                  Prompt for password"
  echo "  -d, --dbname=DBNAME             Database to reindex"
  echo "  -a, --all                       Reindex all databases"
  echo "  -t, --table=TABLE               Reindex specific table only"
  echo "  -i, --index=INDEX               Reindex specific index only"
  echo "  -e, --echo                      Show the command(s) sent to the backend"
  echo "  -q, --quiet                     Don't write any output"
  echo
  echo "Read the description of the SQL command REINDEX for details."
  echo
  exit 0
}

# -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- #
# Program Body
# -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- #

CMDNAME=`basename "$0"`
PATHNAME=`echo $0 | sed "s,$CMDNAME\$,,"`

# Try valiantly to get the location of psql, since you can't ever
# really know where it has been placed.  We'll start by trying the
# path.  If that fails, we'll try the directory where this script
# resides.  Then on to whereis, and finally locate.  Wish us luck.

if x=`psql -V 2>/dev/null | grep psql`; then
  PSQL='psql'
elif [ -f ${PATHNAME}psql ]; then
  PSQL=${PATHNAME}psql;
elif x=`whereis -b psql 2>/dev/null | sed 's/.* //'`; then
  PSQL=$x
elif x=`locate -r bin/psql$ -n 1 2>/dev/null`; then
  PSQL=$x
else
  echo "$CMDNAME: Could not find psql to talk to postgres installation."
  echo "Please make sure psql is in your path, or that this script is in"
  echo "the same directory as psql was installed."
  exit 1
fi

# Now, go through all of our command-line options and get each operation
# we said we'd accept in the usage listing.

while [ "$#" -gt 0 ]
do
  # Show help.
  case "$1" in
    --help|-\?)
      usage
      exit 0
      ;;

  # All of the following are postgres options.  We can pass them on
  # directly, without interpreting them in any way.  We don't care.
  # Anything that allows a space, we'll get the next *two* arguments
  # and make sure to pass those along.

    --host|-h|-p|--port|-U|--username)
      PSQLOPT="$PSQLOPT $1 $2"
      shift
      ;;
    -h*|--host=*|-p*|--port=*|-U*|--username=*|-W|--password)
      PSQLOPT="$PSQLOPT $1"
      ;;

  # From this point on, we're setting options that are required for
  # or only valid in This script.  This includes which database(s) to
  # reindex, which tables, or which indexes, and so on.

    # Echoing.  We'll *not* use this in queries we use to get lists.
    --echo|-e)
      ECHOOPT="-e"
      ;;

    # Do not echo messages.
    --quiet|-q)
      ECHOOPT="-q"
      quiet=1
      ;;

    # Reindex all databases, all tables, all applicable indexes.
    --all|-a)
      alldb=1
      ;;

    # Database to connect to, if not all of them.
    --dbname|-d)
      dbname="$2"
      shift
      ;;
    -d*)
      dbname=`echo "$1" | sed 's/^-d/'`
      ;;
    --dbname=*)
      dbname=`echo "$1" | sed 's/^--dbname=//'`
      ;;

    # Reindex specific Table.  Disables index reindexing.
    --table|-t)
      table="$2"
      shift
      ;;
    -t*)
      table=`echo "$1" | sed 's/^-t//'`
      ;;
    --table=*)
      table=`echo "$1" | sed 's/^--table=//'`
      ;;

    # Reindex specific index.  Disables table reindexing.
    --index|-i)
      index="$2"
      shift
      ;;
    -i*)
      index=`echo "$1" | sed 's/^-i//'`
      ;;
    --index=*)
      index=`echo "$1" | sed 's/^--index=//'`
      ;;

    # Yeah, no options?  Whine, and show usage.
    -*)
      echo "$CMDNAME: invalid option: $1" 1>&2
      usage;
      exit 1
      ;;

    # Finally, it's possible that the database name was just the last
    # unlabeled option.  So, let's get that.
    *)
      dbname="$1"
      ;;
  esac

  shift # Shift off each argument as we loop.

done

# Get a list of all databases we'll be using.  This first case is if we
# were asked to do all databases.
if [ "$alldb" ]; then

  if [ "$dbname" ] || [ "$index" ] || [ "$table" ]; then
    echo "$CMDNAME: cannot reindex all databases and a specific database," 1>&2
    echo " table, or index at the same time." 1>&2
    exit 1
  fi

  # Execute a command to pull back all databases the user specified can
  # connect to.  That's the list we'll be using.  It's also why it's
  # a good idea for this to be run as a super-user.
  sql='SELECT datname FROM pg_database WHERE datallowconn'
  dbname=`$PSQL $PSQLOPT -q -t -A -d postgres -c "$sql"`

# Ok, if it's not all databases, make sure at least one database is
# specified before continuing.
elif [ -z "$dbname" ]; then
  echo "$CMDNAME: missing required argument: database name" 1>&2
  usage;
  exit 1
fi

# No.  We can't reindex a specific index and table at the same time.
# Complain about this, and move on.
if [ "$table" ] && [ "$index" ]; then
  echo "$CMDNAME: cannot reindex a specific table and a specific index" 1>&2
  echo "at the same time." 1>&2
  exit 1
fi

# If index was selected, reindex that index.
if [ "$index" ]; then
  $PSQL $PSQLOPT $ECHOOPT -c "REINDEX INDEX \"$index\"" -d "$dbname"
  if [ "$?" -ne 0 ]; then
    echo "$CMDNAME: reindex index \"$index\" failed" 1>&2
    exit 1
  fi

# Ok, no index.  Is there a specific table to reindex?
elif [ "$table" ]; then
  $PSQL $PSQLOPT $ECHOOPT -c "REINDEX TABLE \"$table\"" -d "$dbname"
  if [ "$?" -ne 0 ]; then
    echo "$CMDNAME: reindex table \"$table\" failed" 1>&2
    exit 1
  fi

# No specific table, no specific index, either we have a specific database,
# or were told to do all databases.  Do it!
else

  # We set IFS to newline only so that the for-loops won't misinterpret
  # spaces in the lists we retrieved via psql.  Note also the use of
  # regclass to handle spaces, mixed-case names, and schema awareness.
  sql="SELECT DISTINCT c.oid::pg_catalog.regclass FROM pg_catalog.pg_index x JOIN pg_catalog.pg_class c ON c.oid = x.indrelid JOIN pg_catalog.pg_namespace n ON c.relnamespace = n.oid WHERE nspname NOT LIKE 'pg\\\\_%'"

  IFS='
'
  for db in $dbname; do

    # Only print which database we're currently reindexing if not in
    # quiet mode, and we're doing more than one database.
    [ "$alldb" ] && [ -z "$quiet" ] && echo "Reindexing $db"

    IFS=' 	
'
    # Get a list of non-system tables that have indexes.
    tables=`$PSQL $PSQLOPT -q -t -A -d "$db" -c "$sql"`

    # Ok, reindex every table in the database.
    IFS='
'
    for tab in $tables; do
	IFS=' 	
'
        $PSQL $PSQLOPT $ECHOOPT -c "REINDEX TABLE $tab" -d "$db"
        if [ "$?" -ne 0 ]; then
          echo "$CMDNAME: reindex table $tab failed" 1>&2
          exit 1
        fi
	IFS='
'
    done

  done

fi

exit 0
