Drop and recreate history trend tables

drop table history_text CASCADE;
drop table history_str CASCADE;
drop table history_log CASCADE;
drop table history_uint CASCADE;
drop table history CASCADE;
drop table trends_uint CASCADE;
drop table trends CASCADE;
CREATE TABLE history (
        itemid                   bigint                                    NOT NULL,
        clock                    integer         DEFAULT '0'               NOT NULL,
        value                    DOUBLE PRECISION DEFAULT '0.0000'          NOT NULL,
        ns                       integer         DEFAULT '0'               NOT NULL
);
CREATE INDEX history_1 ON history (itemid,clock);
CREATE TABLE history_uint (
        itemid                   bigint                                    NOT NULL,
        clock                    integer         DEFAULT '0'               NOT NULL,
        value                    numeric(20)     DEFAULT '0'               NOT NULL,
        ns                       integer         DEFAULT '0'               NOT NULL
);
CREATE INDEX history_uint_1 ON history_uint (itemid,clock);
CREATE TABLE trends (
        itemid                   bigint                                    NOT NULL,
        clock                    integer         DEFAULT '0'               NOT NULL,
        num                      integer         DEFAULT '0'               NOT NULL,
        value_min                DOUBLE PRECISION DEFAULT '0.0000'          NOT NULL,
        value_avg                DOUBLE PRECISION DEFAULT '0.0000'          NOT NULL,
        value_max                DOUBLE PRECISION DEFAULT '0.0000'          NOT NULL,
        PRIMARY KEY (itemid,clock)
);
CREATE TABLE trends_uint (
        itemid                   bigint                                    NOT NULL,
        clock                    integer         DEFAULT '0'               NOT NULL,
        num                      integer         DEFAULT '0'               NOT NULL,
        value_min                numeric(20)     DEFAULT '0'               NOT NULL,
        value_avg                numeric(20)     DEFAULT '0'               NOT NULL,
        value_max                numeric(20)     DEFAULT '0'               NOT NULL,
        PRIMARY KEY (itemid,clock)
);
CREATE TABLE history_str (
        itemid                   bigint                                    NOT NULL,
        clock                    integer         DEFAULT '0'               NOT NULL,
        value                    varchar(255)    DEFAULT ''                NOT NULL,
        ns                       integer         DEFAULT '0'               NOT NULL
);
CREATE INDEX history_str_1 ON history_str (itemid,clock);
CREATE TABLE history_log (
        itemid                   bigint                                    NOT NULL,
        clock                    integer         DEFAULT '0'               NOT NULL,
        timestamp                integer         DEFAULT '0'               NOT NULL,
        source                   varchar(64)     DEFAULT ''                NOT NULL,
        severity                 integer         DEFAULT '0'               NOT NULL,
        value                    text            DEFAULT ''                NOT NULL,
        logeventid               integer         DEFAULT '0'               NOT NULL,
        ns                       integer         DEFAULT '0'               NOT NULL
);
CREATE INDEX history_log_1 ON history_log (itemid,clock);
CREATE TABLE history_text (
        itemid                   bigint                                    NOT NULL,
        clock                    integer         DEFAULT '0'               NOT NULL,
        value                    text            DEFAULT ''                NOT NULL,
        ns                       integer         DEFAULT '0'               NOT NULL
);
CREATE INDEX history_text_1 ON history_text (itemid,clock);