#!/bin/bash

# DCS 20586 - renames the column "max_usability_blk" to "kdp_coeff_rain_hail"
#             in the DSAAdapt table of the IHFS db
#
#
# Author: paul tilles
# May 7,2018

psql=/awips2/psql/bin/psql

# get database name(s) 

database=$(${PSQL} -d metadata -U awipsadmin -Aqtc "
    select datname
    from pg_database
    where datistemplate = false
    and datname like 'hd_ob%'
    ")

echo INFO: Renaming column in the DSAAdapt table

for IH_DB_NAME in ${database}
    do

       echo INFO: Database name is $IH_DB_NAME

       has_column=$(${psql} -U awipsadmin -d $IH_DB_NAME -Atc "
           SELECT EXISTS(
               SELECT 1 FROM information_schema.columns c
               WHERE c.table_name = 'dsaadapt'
               AND c.column_name = 'kdp_coeff_rain_hail'
               );")

       if [[ "${has_column}" == "f" ]]; then
           ${psql} -U awipsadmin -d $IH_DB_NAME -Atc "
               BEGIN TRANSACTION;                
               ALTER TABLE dsaadapt RENAME COLUMN max_usability_blk TO kdp_coeff_rain_hail;
               C       OMMIT TRANSACTION;
               "
       elif [[ "${has_column}" == "t" ]]; then
           echo WARN: Column kdp_coeff_rain_hail already exists within $IH_DB_NAME.dsaadapt. Do nothing.
       else
           echo ERROR: Failed to query the $IH_DB_NAME database.
       fi
    done

echo INFO: Done.