Create a postgresql Partition Table. Create a postgresql partition table.

Create a postgresql Partition Table. Create a postgresql partition table.

In postgresql, there is no partition table creation command. It is created by creating rules such as inherited tables and constraints. The steps are cumbersome and troublesome, and a method is encapsulated. To create a partition table:

CREATE TABLE "odl"."user_action_fatt0" ("date_id" numeric(8,0),"chnl_id" numeric(2,0),"user_acct_type" numeric(2,0),"user_id" numeric(19,0),"cont_id" numeric(19,0),"act_id" numeric(5,0),"act_value" numeric)

Create a partition function

CREATE FUNCTION "public"."partition_generate_numeric"(IN tablename varchar, IN start_date varchar, IN end_date varchar, IN ptype varchar, IN pcolumn varchar) RETURNS "text"     AS $BODY$    import re    import datetime    def udf_date_add(lstr,day):        s = datetime.datetime.strptime(lstr, "%Y%m%d")        s = s+datetime.timedelta(days=day)        return str(s).replace('-','')[0:8]    startdate=start_date    enddate=end_date    if ptype not in('mon','day'):        return "error:\tptype only support 'mon' or 'day'"    if ptype=='day':        if not re.match('[0-9]{8}',startdate):            return "error:\tstartdate need 20130101 format"        if not re.match('[0-9]{8}',enddate):            return "error:\tenddate need 20130101 format"    try:                                                                                                              table_name = tablename.lower().split('.')[1]        table_schema = tablename.lower().split('.')[0]                                                    except (IndexError):                                            return 'error:\ttablename need "tableschema.table_name" format'     while True:        #1)create the partition table        sql = """create table """+table_schema+"""."""+table_name+"""_"""+startdate+""" (                    check (""" + pcolumn + """ >= (""" + startdate + """::numeric) AND """ + pcolumn + """ < (""" + udf_date_add(startdate,1) + """::numeric))                       ) INHERITS ("""+table_schema+"""."""+table_name+""")"""        #plpy.info(sql)        try:            plpy.execute(sql)        except:            pass        #2)create the index for the partition table        sql = """create index """+table_name+"""_"""+startdate+"""_"""+pcolumn+""" on """+table_schema+"""."""+table_name+"""_"""+startdate+""" ("""+pcolumn+""")"""        #plpy.info(sql)        try:            plpy.execute(sql)        except:            pass        startdate=udf_date_add(startdate,1)        if startdate>enddate:            break     #2.0)create the error table    sql = """create table """+table_schema+"""."""+table_name+"""_error_"""+pcolumn+""" as select * from """+table_schema+"""."""+table_name+""" limit 0    """    try:        plpy.execute(sql)    except:        pass    #3)create the trigger for the partition table    trigger_tmp=""     startdate=start_date    while True:        trigger_tmp=trigger_tmp+"""elsif (NEW."""+pcolumn+""" >= ("""+startdate+"""::numeric) and NEW."""+pcolumn+""" < ("""+udf_date_add(startdate,1)+"""::numeric) ) THEN                  INSERT INTO """+table_schema+"""."""+table_name+"""_"""+startdate+""" VALUES (NEW.*);             """        startdate=udf_date_add(startdate,1)        if startdate>udf_date_add(enddate,365):            break    trigger_tmp=trigger_tmp+"""            else                  INSERT INTO """+table_schema+"""."""+table_name+"""_error_"""+pcolumn+""" VALUES (NEW.*);               end if;                    """    trigger_tmp=trigger_tmp[3:]    sql ="""     CREATE OR REPLACE FUNCTION """+table_schema+"""."""+table_name+"""_insert_trigger()                              RETURNS TRIGGER AS         $PROC$        BEGIN              """+trigger_tmp+"""            RETURN NULL;          END;          $PROC$        LANGUAGE plpgsql    """    #plpy.info(sql)    plpy.execute(sql)    #4)create the insert trigger    sql = """    CREATE TRIGGER insert_"""+table_name+"""_trigger    BEFORE INSERT ON """+table_schema+"""."""+table_name+"""    FOR EACH ROW EXECUTE PROCEDURE """+table_schema+"""."""+table_name+"""_insert_trigger()    """    #plpy.info(sql)    try:        plpy.execute(sql)    except:        pass    return "success"$BODY$    LANGUAGE plpythonu    COST 100    CALLED ON NULL INPUT    SECURITY INVOKER    VOLATILE;ALTER FUNCTION "public"."partition_generate_numeric"(IN tablename varchar, IN start_date varchar, IN end_date varchar, IN ptype varchar, IN pcolumn varchar) OWNER TO "brecom";