例) 
select * from test;
if [ $SQLCODE -eq $SQL_OK ]; then
   ...
fi

    
  exec_sql -h select         --- SELECT文のヘルプ
  exec_sql -h 'create table' --- CRAETE TABLE文のヘルプ
  exec_sql -h HELP           --- SELECT,CREATEなどの一覧表示
  exec_sql -h ALL            --- SELECT,CREATEなどの全詳細
  exec_sql -h OPTION         --- オプションだけの一覧
  exec_sql -h ERRNO          --- SQLエラーコード一覧表示
  exec_sql -h EXAMPLE        --- 使用例

    exec_sql -l da    --- データベース名一覧表示
    exec_sql -l ta    --- テーブル名とビユー名一覧表示
    exec_sql -l in    --- インデックス名一覧表示
    exec_sql -l se    --- シークエンステーブル名一覧表示
    exec_sql -l gr    --- 権限一覧表示
    exec_sql -l fu    --- FUNCTION名一覧表示
    exec_sql -l op    --- オペレータ一覧表示
    exec_sql -l ty    --- データ型一覧表示
    exec_sql -l sy    --- システムテーブル一覧
    exec_sql -p table名 - テーブルの列名、データ型などの表示
    exec_sql -p '*'   --- 全テーブルの列名、データ型などの表示

  h  [SQL]: help <SQL> syntax or all SQL_commands
  o       : help OPTIONs of 'exec_sql' function
  v       : print PGBASH VERSION
  s       : print STATUS after SQL execution
  u       : list all USERs
  l       : list all DATABASEs
  m       : list all CONNECTIONs
  d  [TBL]: list tables,indices,columns in <TaBLe>, or all tables
  dt      : list only TABLEs
  di      : list only INDEXes
  ds      : list only SEQUENCEs
  dg      : list GRANT/REVOKE permissions
  dA      : list AGGREGATEs
  dD [obj]: list DESCRIPTIONs for <TAble,FIeld,TYp,FU,OP>, or all
  dF      : list PosgreSQL FUNCTIONs
  dO      : list OPERATORs
  dS      : list SYSTEM tables and indexes
  dT      : list TYPEs

  ・CONNECT TO dbname[@server[:port]] | DEFAULT  
                     [AS connect_name] [USER user_name [password]];
  ・DISCONNECT connect_name|CURRENT|DEFAULT|ALL;
  ・SET CONNECTION connect_name|DEFAULT;

  例) connect to postgres1 as db1 user postgres xxxxxxxx;
      connect to postgres2 as db2 ;   ....ログインのユーザ名が使用される
      set connection db1;
      select * from test1;
      set connection db2;
      select * from test2;
      disconenct all;

    connect to default;
    connect to postgres@www2.psn.ne.jp:5432  as db1;
    connect to admin@xxx.psn.ne.jp as db2 user admin;
    exec_sql -mL (対話型環境では m )
    # Connected Databases List (C: current database is '*')
    +---+--------------+-----------+------------------------------+
    | C | connect_name | user_name | target_name                  |
    +---+--------------+-----------+------------------------------+
    |   | _DEFAULT_    | postgres  | postgres:5432                |
    |   | db1          | postgres  | postgres@www.psn.ne.jp:5432  |
    | * | db2          | admin     | admin@xxx.psn.ne.jp:5432     |
    +---+--------------+-----------+------------------------------+
    (3 rows)

  例) connect to postgres1 as db1;
      connect to postgres2 as db2;
      connect to postgres1 as db3;
      set connection db1;    <-------------- db1をカレントに指定
      exec_sql -d db2 "select * from test2" <-- db2の接続
      exec_sql        "select * from test1" <-- db1の接続
      exec_sql -d db3 "select * from test2" <-- db3の接続
      select * from test;                   <-- db1の接続

  FETCH [FORWARD|BACKWARD] [number|ALL] [IN cursorname]
        [INTO :host_var1 [[INDICATOR] :ind_var1], ...
              :host_varN [[INDICATOR] :ind_varN]];

begin; 
declare cur cursor for select * from test;
declares -i x ; let x=0;  while ((x < 10))  
do
   fetch in cur into :CODE indicator :IND_C,
                     :NAME:IND_N, :ADDRESS :IND_A;
    if (( SQLCODE == SQL_OK )); then
        if ((IND_N != SQL_NULL || IND_A != SQL_NULL)); then
            echo "$CODE, $NAME, $ADDRESS"
            let x=x+1
        fi
    else
        if(( SQLCODE == SQL_NOT_FOUND )); then
                let x=11
        else
                echo "$SQLERRMC"
                let x=x+1
        fi
    fi
done
end;

  begin;
  insert into tbname(col1,col2) values(読み込まれたデータ1)
  insert into tbname(col1,col2) values(読み込まれたデータ2)
  ...
  end;

  begin;
  declare copy_cur00 cursor for select col1,col2 from tbname;
  fetch 300 in copy_cur00 >> /tmp/oo
  fetch 300 in copy_cur00 >> /tmp/oo
  ..
  end;

  $SQLOID     :(整数型) 最新のinsertのOIDの値
　$SQLCODE    :(整数型) SQLエラーコード (9.エラーコード参照)
                 0    --- 正常終了          
                 100  --- EOF(Eond Of File)  
                 負値 --- SQLエラー         
  $SQLERRMC   :(文字型) SQLエラーメッセージ(最大70字)
　$SQLERRML   :(整数型) SQL エラーメッセージの長さ(<70)
  $SQLERRD2   :(整数型) 検索結果の行数(PQntuples()の値)
  $SQLERRD3   :(整数型) 検索結果の列数(PQnfields()の値)
  $SQLNTUPLE  :(整数型) SQLERRD2と同じ
  $SQLNFIELD  :(整数型) SQLERRD3と同じ

  ${SQLFIELDNAME[i]} : 列名並び(i は 0 から SQLNFIELD-1 まで)

    SQL_OK                 :    0 : normal end. 
    SQL_NOT_FOUND          :  100 : EOF(End Of File). 
    SQL_SYSTEM_ERROR       : -200 : system error. 
    SQL_TOO_MANY_ARGUMENTS : -201 : too many arguments in fetch_stmt. 
    SQL_TOO_FEW_ARGUMENTS  : -202 : too few  arguments in fetch_stmt. 
    SQL_CONNECT_ERROR      : -203 : Database connection error. 
    SQL_INVALID_STMT       : -230 : invalid statements. 
    SQL_READONLY_SHELLVAR  : -231 : can not set read-only shell variable. 
    SQL_DB_NOT_OPEN        : -232 : DB not open. 
    SQL_CNAME_NOT_FOUND    : -233 : connect-name not found. 
    SQL_CNAME_ALREADY_USE  : -234 : connect-name already exist. 
    SQL_INVALID_COMMAND    : -235 : invalid command. 
    SQL_BAD_RESPONSE       : -400 : bad response(backend maybe died)." 
    SQL_EMPTY_QUERY        : -401 : empty query (backend lost query). 
    SQL_CONNECTION_BAD     : -402 : connection bad(disconnect backend)" 
    SQL_FATAL_ERROR        : -403 : query fatal error   (SQL error on backend) 
　  SQL_NONFATAL_ERROR     : -404 : query nonfatal error(SQL error on backend) 
    SQL_NULL               :   -1 : indicator is NULL. 

　(例)
　insert into test values(111,'aaa','bbb');
  if(( SQLCODE < SQL_OK ))
  then
     echo $SQLERRMC
  fi

# SQL status (shell variable)                           
  SQLCODE   = -403   (SQL error code)
  SQLNTUPLES= 0      (number of tuples)
  SQLNFIELDS= 0      (number of fields)
  SQLERRML  = 38     (length of SQLERRMC)     
  SQLERRMC  = ERROR:  testxxx: Table does not exist.