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Diffstat (limited to '')
-rw-r--r-- | dependencies/pkg/mod/github.com/mattn/go-sqlite3@v1.14.16/_example/limit/limit.go | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/dependencies/pkg/mod/github.com/mattn/go-sqlite3@v1.14.16/_example/limit/limit.go b/dependencies/pkg/mod/github.com/mattn/go-sqlite3@v1.14.16/_example/limit/limit.go new file mode 100644 index 0000000..bcba819 --- /dev/null +++ b/dependencies/pkg/mod/github.com/mattn/go-sqlite3@v1.14.16/_example/limit/limit.go @@ -0,0 +1,113 @@ +package main + +import ( + "database/sql" + "fmt" + "log" + "os" + "strings" + + "github.com/mattn/go-sqlite3" +) + +func createBulkInsertQuery(n int, start int) (query string, args []interface{}) { + values := make([]string, n) + args = make([]interface{}, n*2) + pos := 0 + for i := 0; i < n; i++ { + values[i] = "(?, ?)" + args[pos] = start + i + args[pos+1] = fmt.Sprintf("こんにちは世界%03d", i) + pos += 2 + } + query = fmt.Sprintf( + "insert into foo(id, name) values %s", + strings.Join(values, ", "), + ) + return +} + +func bulkInsert(db *sql.DB, query string, args []interface{}) (err error) { + stmt, err := db.Prepare(query) + if err != nil { + return + } + + _, err = stmt.Exec(args...) + if err != nil { + return + } + + return +} + +func main() { + var sqlite3conn *sqlite3.SQLiteConn + sql.Register("sqlite3_with_limit", &sqlite3.SQLiteDriver{ + ConnectHook: func(conn *sqlite3.SQLiteConn) error { + sqlite3conn = conn + return nil + }, + }) + + os.Remove("./foo.db") + db, err := sql.Open("sqlite3_with_limit", "./foo.db") + if err != nil { + log.Fatal(err) + } + defer db.Close() + + sqlStmt := ` + create table foo (id integer not null primary key, name text); + delete from foo; + ` + _, err = db.Exec(sqlStmt) + if err != nil { + log.Printf("%q: %s\n", err, sqlStmt) + return + } + + if sqlite3conn == nil { + log.Fatal("not set sqlite3 connection") + } + + limitVariableNumber := sqlite3conn.GetLimit(sqlite3.SQLITE_LIMIT_VARIABLE_NUMBER) + log.Printf("default SQLITE_LIMIT_VARIABLE_NUMBER: %d", limitVariableNumber) + + num := 400 + query, args := createBulkInsertQuery(num, 0) + err = bulkInsert(db, query, args) + if err != nil { + log.Fatal(err) + } + + smallLimitVariableNumber := 100 + sqlite3conn.SetLimit(sqlite3.SQLITE_LIMIT_VARIABLE_NUMBER, smallLimitVariableNumber) + + limitVariableNumber = sqlite3conn.GetLimit(sqlite3.SQLITE_LIMIT_VARIABLE_NUMBER) + log.Printf("updated SQLITE_LIMIT_VARIABLE_NUMBER: %d", limitVariableNumber) + + query, args = createBulkInsertQuery(num, num) + err = bulkInsert(db, query, args) + if err != nil { + if err != nil { + log.Printf("expect failed since SQLITE_LIMIT_VARIABLE_NUMBER is too small: %v", err) + } + } + + bigLimitVariableNumber := 999999 + sqlite3conn.SetLimit(sqlite3.SQLITE_LIMIT_VARIABLE_NUMBER, bigLimitVariableNumber) + limitVariableNumber = sqlite3conn.GetLimit(sqlite3.SQLITE_LIMIT_VARIABLE_NUMBER) + log.Printf("set SQLITE_LIMIT_VARIABLE_NUMBER: %d", bigLimitVariableNumber) + log.Printf("updated SQLITE_LIMIT_VARIABLE_NUMBER: %d", limitVariableNumber) + + query, args = createBulkInsertQuery(500, num+num) + err = bulkInsert(db, query, args) + if err != nil { + if err != nil { + log.Fatal(err) + } + } + + log.Println("no error if SQLITE_LIMIT_VARIABLE_NUMBER > 999") +} |