[statspro] Restart drop db (#8350)

* [statspro] restart only inits stats database if missing

* fix test

go/libraries/doltcore/sqle/statspro/configure.go

@@ -147,8 +147,6 @@ func (p *Provider) Load(ctx *sql.Context, fs filesys.Filesys, db dsess.SqlDataba
 		}
 	}
 
-	p.mu.Lock()
-	defer p.mu.Unlock()
 	p.setStatDb(strings.ToLower(db.Name()), statsDb)
 	return
 }

go/libraries/doltcore/sqle/statspro/initdbhook.go

@@ -37,15 +37,15 @@ func NewStatsInitDatabaseHook(
 		denv *env.DoltEnv,
 		db dsess.SqlDatabase,
 	) error {
-		statsDb, err := statsProv.sf.Init(ctx, db, statsProv.pro, denv.FS, env.GetCurrentUserHomeDir)
-		if err != nil {
-			ctx.GetLogger().Debugf("statistics load error: %s", err.Error())
-			return nil
+		dbName := strings.ToLower(db.Name())
+		if _, ok := statsProv.getStatDb(dbName); !ok {
+			statsDb, err := statsProv.sf.Init(ctx, db, statsProv.pro, denv.FS, env.GetCurrentUserHomeDir)
+			if err != nil {
+				ctx.GetLogger().Debugf("statistics load error: %s", err.Error())
+				return nil
+			}
+			statsProv.setStatDb(dbName, statsDb)
 		}
-		statsProv.mu.Lock()
-		statsProv.setStatDb(strings.ToLower(db.Name()), statsDb)
-		statsProv.mu.Unlock()
-
 		ctx.GetLogger().Debugf("statistics refresh: initialize %s", name)
 		return statsProv.InitAutoRefresh(ctxFactory, name, bThreads)
 	}

go/libraries/doltcore/sqle/statspro/stats_provider.go

@@ -186,6 +186,8 @@ func (p *Provider) GetTableDoltStats(ctx *sql.Context, branch, db, table string)
 }
 
 func (p *Provider) setStatDb(name string, db Database) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
 	p.statDbs[name] = db
 }
 

integration-tests/bats/stats.bats

@@ -130,6 +130,26 @@ teardown() {
     [ "$status" -eq 1 ]
 }
 
+@test "stats: restart in shell doesn't drop db, issue#8345" {
+    cd repo2
+
+    dolt sql -q "insert into xy values (0,0), (1,1), (2,2), (3,3), (4,4)"
+    dolt sql -q "insert into ab values (0,0), (1,1), (2,2), (3,3), (4,4)"
+    dolt sql -q "ANALYZE table xy, ab"
+    run dolt sql -r csv <<EOF
+select count(*) from dolt_statistics;
+set @@GLOBAL.dolt_stats_auto_refresh_interval = 2;
+call dolt_stats_restart();
+select count(*) from dolt_statistics;
+select sleep(3);
+select count(*) from dolt_statistics;
+EOF
+    [ "${lines[1]}" = "4" ]
+    [ "${lines[5]}" = "4" ]
+    [ "${lines[9]}" = "4" ]
+    [ "$status" -eq 0 ]
+}
+
 @test "stats: stats roundtrip restart" {
     cd repo2
 
@@ -383,6 +403,7 @@ SQL
     dolt sql <<SQL
 use repo2;
 insert into xy values (0,0);
+analyze table xy;
 SQL
 
     sleep 1