Add example for arbitrary columns

examples/arbitrary_column_names/main.go

@@ -0,0 +1,194 @@
+// Sometimes you need to run queries that join tables which produce arbitrary column names.
+// This file shows how to handle arbitrary query column names by assigning aliases, then scanning rows into a slice array that contains structs with embedded structs.
+// Take note of the relationship between struct tags and query aliasing.
+package main
+
+import (
+	"fmt"
+	"log"
+	"time"
+
+	"github.com/jmoiron/sqlx"
+	_ "github.com/lib/pq"
+)
+
+var schema = `
+CREATE TABLE TEAM
+(
+    ID         INTEGER PRIMARY KEY,
+    NAME VARCHAR(35) UNIQUE,
+    CREATED_AT timestamp   NOT NULL DEFAULT now(),
+    UPDATED_AT timestamp   NOT NULL DEFAULT now(),
+    DELETED_AT timestamp
+);
+
+CREATE TABLE GAME
+(
+    ID             INTEGER PRIMARY KEY,
+    HOME_TEAM_ID   INTEGER    NOT NULL,
+    AWAY_TEAM_ID   INTEGER    NOT NULL,
+    GAME_DATE_TIME timestamp,
+    CREATED_AT     timestamp  NOT NULL DEFAULT now(),
+    UPDATED_AT     timestamp  NOT NULL DEFAULT now(),
+    DELETED_AT     timestamp,
+    foreign key (HOME_TEAM_ID) references TEAM (ID),
+    foreign key (AWAY_TEAM_ID) references TEAM (ID)
+);
+
+CREATE TABLE GAME_OFFENSIVE_STATS
+(
+    ID                        SERIAL PRIMARY KEY,
+    TEAM_ID                   INTEGER   NOT NULL,
+    GAME_ID                   INTEGER   NOT NULL,
+    OFFENSE_AT_BATS           REAL       NOT NULL DEFAULT 0,
+    CREATED_AT                timestamp NOT NULL DEFAULT now(),
+    UPDATED_AT                timestamp NOT NULL DEFAULT now(),
+    DELETED_AT                timestamp,
+    foreign key (TEAM_ID) references TEAM (ID),
+    foreign key (GAME_ID) references GAME (ID)
+);
+
+CREATE TABLE GAME_DEFENSIVE_STATS
+(
+    ID                      SERIAL PRIMARY KEY,
+    TEAM_ID                 INTEGER   NOT NULL,
+    GAME_ID                 INTEGER   NOT NULL,
+    DEFENSE_ASSISTS         REAL       NOT NULL DEFAULT 0,
+    CREATED_AT              timestamp NOT NULL DEFAULT now(),
+    UPDATED_AT              timestamp NOT NULL DEFAULT now(),
+    DELETED_AT              timestamp,
+    foreign key (TEAM_ID) references TEAM (ID),
+    foreign key (GAME_ID) references GAME (ID)
+);
+
+CREATE TABLE GAME_PITCHING_STATS
+(
+    ID                         SERIAL PRIMARY KEY,
+    TEAM_ID                    INT       NOT NULL,
+    GAME_ID                    INT       NOT NULL,
+    PITCHING_AIR_OUTS          REAL       NOT NULL DEFAULT 0,
+    CREATED_AT                 timestamp NOT NULL DEFAULT now(),
+    UPDATED_AT                 timestamp NOT NULL DEFAULT now(),
+    DELETED_AT                 timestamp,
+    foreign key (TEAM_ID) references TEAM (ID),
+    foreign key (GAME_ID) references GAME (ID)
+);`
+
+const getTeamStats = `select g.id as "game.id",
+       g.home_team_id as "game.home_team_id",
+       g.away_team_id as "game.away_team_id",
+       g.game_date_time as "game.game_date_time",
+       g.created_at as "game.created_at",
+       g.updated_at as "game.updated_at",
+       g.deleted_at as "game.deleted_at",
+       gds.id as "defense.id",
+       gds.team_id as "defense.team_id",
+       gds.game_id as "defense.game_id",
+       gds.defense_assists as "defense.defense_assists",
+       gds.created_at as "defense.created_at",
+       gds.updated_at as "defense.updated_at",
+       gds.deleted_at as "defense.deleted_at",
+       gos.id as  "offense.id",
+       gos.team_id as "offense.team_id",
+       gos.game_id as "offense.game_id",
+       gos.offense_at_bats as "offense.offense_at_bats",
+       gos.created_at as "offense.created_at",
+       gos.updated_at as "offense.updated_at",
+       gos.deleted_at as "offense.deleted_at",
+       gps.id as "pitching.id",
+       gps.team_id as "pitching.team_id",
+       gps.game_id as "pitching.game_id",
+       gps.pitching_air_outs as "pitching.pitching_air_outs",
+       gps.created_at as "pitching.created_at",
+       gps.updated_at as "pitching.updated_at",
+       gps.deleted_at as "pitching.deleted_at"
+from game as g
+         inner join GAME_DEFENSIVE_STATS as gds on g.id = gds.game_id
+         inner join GAME_OFFENSIVE_STATS as gos on gds.game_id = gos.game_id and gds.team_id = gos.team_id
+         inner join GAME_PITCHING_STATS as gps on gos.game_id = gps.game_id and gos.team_id = gps.team_id`
+
+type (
+	GameStats struct {
+		ID           int        `json:"id,omitempty" db:"id"`
+		AwayTeam     int        `json:"awayTeamId" db:"away_team_id"`
+		HomeTeam     int        `json:"homeTeamId" db:"home_team_id"`
+		GameDateTime time.Time  `json:"gameDateTime" db:"game_date_time"`
+		Season       string     `json:"season,omitempty" db:"season"`
+		CreatedAt    time.Time  `json:"createdAt" db:"created_at"`
+		UpdatedAt    time.Time  `json:"updatedAt" db:"updated_at"`
+		DeletedAt    *time.Time `json:"deletedAt" db:"deleted_at"`
+	}
+	OffenseStats struct {
+		ID        int        `json:"ID,omitempty" db:"id"`
+		Team      int        `json:"team,omitempty" db:"team_id"`
+		Game      int        `json:"game,omitempty" db:"game_id"`
+		AtBats    float32    `json:"atBats,omitempty" db:"offense_at_bats"`
+		CreatedAt time.Time  `json:"createdAt" db:"created_at"`
+		UpdatedAt time.Time  `json:"updatedAt" db:"updated_at"`
+		DeletedAt *time.Time `json:"deletedAt" db:"deleted_at"`
+	}
+	DefenseStats struct {
+		ID        int        `json:"ID,omitempty" db:"id"`
+		Team      int        `json:"team,omitempty" db:"team_id"`
+		Game      int        `json:"game,omitempty" db:"game_id"`
+		Assists   float32    `json:"assists,omitempty" db:"defense_assists"`
+		CreatedAt time.Time  `json:"createdAt" db:"created_at"`
+		UpdateAt  time.Time  `json:"updateAT" db:"updated_at"`
+		DeletedAt *time.Time `json:"deletedAt" db:"deleted_at"`
+	}
+	PitchingStats struct {
+		ID        int        `json:"ID,omitempty" db:"id"`
+		Team      int        `json:"team,omitempty" db:"team_id"`
+		Game      int        `json:"game,omitempty" db:"game_id"`
+		AirOuts   float32    `json:"airOuts" db:"pitching_air_outs"`
+		CreatedAt time.Time  `json:"createdAt" db:"created_at"`
+		UpdatedAt time.Time  `json:"updatedAt" db:"updated_at"`
+		DeletedAt *time.Time `json:"deletedAt" db:"deleted_at"`
+	}
+	TeamStats struct {
+		Game     GameStats     `db:"game"`
+		Offense  OffenseStats  `db:"offense"`
+		Defense  DefenseStats  `db:"defense"`
+		Pitching PitchingStats `db:"pitching"`
+	}
+)
+
+func main() {
+
+	db, err := sqlx.Connect("postgres", "user=foo dbname=bar sslmode=disable")
+	if err != nil {
+		log.Fatalln(err)
+	}
+
+	db.MustExec(schema)
+
+	tx := db.MustBegin()
+	tx.MustExec("INSERT INTO team (id, name) VALUES ($1, $2)", 1, "Pittsburgh Pirates")
+	tx.MustExec("INSERT INTO team (id, name) VALUES ($1, $2)", 2, "Baltimore Oriels")
+	tx.MustExec("INSERT INTO game (id, home_team_id, away_team_id, game_date_time) VALUES ($1, $2, $3, $4)", 1, 1, 2, time.Now())
+	tx.MustExec("INSERT INTO GAME_OFFENSIVE_STATS (team_id, game_id, offense_at_bats) VALUES ($1, $2, $3)", 1, 1, 27)
+	tx.MustExec("INSERT INTO GAME_DEFENSIVE_STATS (team_id, game_id, DEFENSE_ASSISTS) VALUES ($1, $2, $3)", 1, 1, 8)
+	tx.MustExec("INSERT INTO GAME_PITCHING_STATS (team_id, game_id, PITCHING_AIR_OUTS) VALUES ($1, $2, $3)", 1, 1, 16)
+
+	err = tx.Commit()
+	if err != nil {
+		fmt.Println(err)
+	}
+
+	var game []GameStats
+	err = db.Select(&game, "SELECT * FROM GAME")
+	if err != nil {
+		fmt.Println(err)
+	}
+	fmt.Printf("%#v\n", game)
+
+	// Query the database, storing results in a []TeamStats
+	var teamStats []TeamStats
+	err = db.Select(&teamStats, getTeamStats)
+	if err != nil {
+		fmt.Println(err)
+	}
+
+	fmt.Printf("%#v\n", teamStats)
+
+}