feat: 新增 DuckDB 方言支持及 SQLite3 自动注册 IF 函数

- 新增 dialect/duckdb 方言，支持 DuckDB SQL 语法 - 新增 schema/dialect/duckdb DDL 操作支持 - dialect/sqlite3: 注册 sqlite3_with_if 驱动，连接时自动注册 IF() 函数 - engine: MakeConnection 对 sqlite3 自动使用带 IF 支持的驱动 - engine: 新增 DBConfig DuckDB 配置项及相关 Option 函数 - 统一各方言测试引用路径
2026-04-16 10:14:46 +08:00
parent c4590cf592
commit 2221ca0ddb
19 changed files with 1270 additions and 62 deletions
@@ -0,0 +1,271 @@
+package duckdb
+
+import (
+	"strings"
+
+	"git.fsdpf.net/go/db"
+	"git.fsdpf.net/go/db/dialect/duckdb"
+	"git.fsdpf.net/go/db/internal/sb"
+	"git.fsdpf.net/go/db/schema"
+	"git.fsdpf.net/go/db/sqlgen"
+)
+
+type DuckDB struct {
+	db  *db.Database
+	esg sqlgen.ExpressionSQLGenerator
+}
+
+var duckdbDefaultModifiers = []string{
+	"Nullable", "Default", "Increment", "Comment",
+}
+
+func (this DuckDB) GetColumnListing(table string) ([]string, error) {
+	cols := []string{}
+	err := this.db.From(db.S("information_schema").Table("columns")).Where(
+		db.C("table_name").Eq(table),
+	).Pluck(&cols, "column_name")
+	return cols, err
+}
+
+func (this DuckDB) TableExists(table string) (bool, error) {
+	result, err := this.db.From(db.S("information_schema").Table("tables")).Where(db.Ex{
+		"table_name": table,
+		"table_type": "BASE TABLE",
+	}).Count()
+	return result > 0, err
+}
+
+func (this DuckDB) CompileCreate(bp *schema.Blueprint) []string {
+	temporary := db.L("CREATE")
+	if bp.Temporary {
+		temporary = db.L("CREATE TEMPORARY")
+	}
+	columns := strings.Join(this.getAddedColumns(bp), ",\n")
+	sql := this.GenerateSQL("? TABLE ? (\n?\n)", temporary, db.T(bp.GetTable()), db.L(columns))
+
+	if comment := bp.Comment; comment != "" {
+		sql = sql[:len(sql)-1] + ";" + this.GenerateSQL("\nCOMMENT ON TABLE ? IS ?", db.T(bp.GetTable()), db.V(comment))
+	}
+
+	return []string{sql}
+}
+
+func (this DuckDB) CompileAdd(bp *schema.Blueprint) []string {
+	columns := strings.Join(schema.PrefixArray("ADD COLUMN", this.getAddedColumns(bp)), ",\n")
+	sql := this.GenerateSQL("ALTER TABLE ?\n?", db.T(bp.GetTable()), db.L(columns))
+	return []string{sql}
+}
+
+func (this DuckDB) CompileChange(bp *schema.Blueprint) []string {
+	sqls := []string{}
+	for _, column := range bp.GetChangedColumns() {
+		name := column.Name
+		rename := column.Name
+		if column.GetRename() != "" {
+			rename = column.GetRename()
+		}
+
+		// DuckDB 需要分别修改类型和约束
+		if rename != name {
+			sqls = append(sqls, this.GenerateSQL("ALTER TABLE ? RENAME COLUMN ? TO ?",
+				db.T(bp.GetTable()), db.C(name), db.C(rename)))
+		}
+
+		// 修改类型
+		sql := this.GenerateSQL("ALTER TABLE ? ALTER COLUMN ? TYPE ?",
+			db.T(bp.GetTable()), db.C(rename), db.L(this.GetColumnType(column)))
+		sqls = append(sqls, sql)
+
+		// 修改 nullable
+		if column.IsNullable() {
+			sqls = append(sqls, this.GenerateSQL("ALTER TABLE ? ALTER COLUMN ? DROP NOT NULL",
+				db.T(bp.GetTable()), db.C(rename)))
+		} else {
+			sqls = append(sqls, this.GenerateSQL("ALTER TABLE ? ALTER COLUMN ? SET NOT NULL",
+				db.T(bp.GetTable()), db.C(rename)))
+		}
+
+		// 修改默认值
+		v := column.GetDefault()
+		if v != nil {
+			sqls = append(sqls, this.GenerateSQL("ALTER TABLE ? ALTER COLUMN ? SET DEFAULT ?",
+				db.T(bp.GetTable()), db.C(rename), v))
+		} else if column.IsUseCurrent() {
+			sqls = append(sqls, this.GenerateSQL("ALTER TABLE ? ALTER COLUMN ? SET DEFAULT CURRENT_TIMESTAMP",
+				db.T(bp.GetTable()), db.C(rename)))
+		}
+	}
+	return sqls
+}
+
+func (this DuckDB) CompileDropColumn(bp *schema.Blueprint) []string {
+	columns := []string{}
+	for _, item := range bp.GetCommands() {
+		if item.Type != "dropColumn" {
+			continue
+		}
+		for _, col := range item.Columns {
+			columns = append(columns, this.GenerateSQL("DROP COLUMN ?", db.C(col)))
+		}
+	}
+	sql := this.GenerateSQL("ALTER TABLE ?\n?", db.T(bp.GetTable()), db.L(strings.Join(columns, ",\n")))
+	return []string{sql}
+}
+
+func (this DuckDB) CompileDrop(bp *schema.Blueprint) []string {
+	return []string{this.GenerateSQL("DROP TABLE ?", db.T(bp.GetTable()))}
+}
+
+func (this DuckDB) CompileDropIfExists(bp *schema.Blueprint) []string {
+	return []string{this.GenerateSQL("DROP TABLE IF EXISTS ?", db.T(bp.GetTable()))}
+}
+
+func (this DuckDB) CompileRename(bp *schema.Blueprint) []string {
+	toName := ""
+	commands := bp.GetCommands()
+	if len(commands) == 0 {
+		panic("new table undefined")
+	}
+	toName = commands[0].To
+	if toName == "" {
+		panic("new table undefined")
+	}
+	return []string{this.GenerateSQL("ALTER TABLE ? RENAME TO ?", db.T(bp.GetTable()), db.T(toName))}
+}
+
+func (this DuckDB) CompileModifyComment(bp *schema.Blueprint) []string {
+	return []string{
+		this.GenerateSQL("COMMENT ON TABLE ? IS ?", db.T(bp.GetTable()), db.V(bp.Comment)),
+	}
+}
+
+func (this DuckDB) addModifiers(sql string, bp *schema.Blueprint, column *schema.ColumnDefinition) string {
+	for _, modifier := range duckdbDefaultModifiers {
+		sql += this.GetColumnModifier(modifier, bp, column)
+	}
+	return sql
+}
+
+func (this DuckDB) GetColumnType(column *schema.ColumnDefinition) string {
+	switch column.Type {
+	case "char":
+		return this.GenerateSQL("CHAR(?)", column.Length)
+	case "string":
+		return this.GenerateSQL("VARCHAR(?)", column.Length)
+	case "text":
+		return "TEXT"
+	case "integer":
+		return "INTEGER"
+	case "bigInteger":
+		return "BIGINT"
+	case "smallInteger":
+		return "SMALLINT"
+	case "tinyInteger":
+		return "TINYINT"
+	case "decimal":
+		return this.GenerateSQL("DECIMAL(?,?)", column.Total, column.Places)
+	case "boolean":
+		return "BOOLEAN"
+	case "enum":
+		// DuckDB 支持 ENUM 类型
+		return this.GenerateSQL("VARCHAR(?)", column.Length)
+	case "json":
+		return "JSON"
+	case "binary":
+		return "BLOB"
+	case "datetime":
+		return "TIMESTAMP"
+	case "timestamp":
+		return "TIMESTAMP"
+	case "date":
+		return "DATE"
+	case "time":
+		return "TIME"
+	case "year":
+		return "SMALLINT"
+	case "uuid":
+		return "UUID"
+	}
+	panic("Unsupported data type: " + column.Type)
+}
+
+func (this DuckDB) GetColumnModifier(modifier string, bp *schema.Blueprint, column *schema.ColumnDefinition) string {
+	switch modifier {
+	case "Nullable":
+		if column.IsNullable() {
+			return " NULL"
+		}
+		return " NOT NULL"
+	case "Default":
+		v := column.GetDefault()
+		if v == nil {
+			if column.IsUseCurrent() {
+				return " DEFAULT CURRENT_TIMESTAMP"
+			}
+			return ""
+		}
+		return this.GenerateSQL(" DEFAULT ?", v)
+	case "Increment":
+		if column.IsAutoIncrement() {
+			// DuckDB 使用 SERIAL 或者 SEQUENCE
+			return " PRIMARY KEY"
+		}
+	case "Comment":
+		// DuckDB 支持列注释，但需要在 CREATE TABLE 后使用 COMMENT ON
+		return ""
+	}
+	return ""
+}
+
+func (this DuckDB) getAddedColumns(bp *schema.Blueprint) (columns []string) {
+	for _, column := range bp.GetAddedColumns() {
+		colType := this.GetColumnType(column)
+		// 对于自增列，使用 SERIAL 类型
+		if column.IsAutoIncrement() {
+			switch column.Type {
+			case "bigInteger":
+				colType = "BIGSERIAL"
+			case "smallInteger":
+				colType = "SMALLSERIAL"
+			default:
+				colType = "SERIAL"
+			}
+		}
+		sql := this.GenerateSQL("? ?", db.C(column.Name), db.L(colType))
+		columns = append(columns, this.addModifiers(sql, bp, column))
+	}
+	return
+}
+
+func (this DuckDB) getChangedColumns(bp *schema.Blueprint) (columns []string) {
+	for _, column := range bp.GetChangedColumns() {
+		name := column.Name
+		rename := column.Name
+		if column.GetRename() != "" {
+			rename = column.GetRename()
+		}
+		sql := this.GenerateSQL("? ?", db.C(rename), db.L(this.GetColumnType(column)))
+		columns = append(columns, this.addModifiers(sql, bp, column))
+		if rename != name {
+			// 需要额外的重命名语句
+			columns = append(columns, this.GenerateSQL("RENAME COLUMN ? TO ?", db.C(name), db.C(rename)))
+		}
+	}
+	return
+}
+
+func (this DuckDB) GenerateSQL(sql string, args ...any) string {
+	sb := sb.NewSQLBuilder(false)
+	this.esg.Generate(sb, db.L(sql, args...))
+	result, _, _ := sb.ToSQL()
+	return result
+}
+
+func init() {
+	schema.RegisterDialect("duckdb", func(db *db.Database) schema.Schema {
+		return &DuckDB{
+			db:  db,
+			esg: sqlgen.NewExpressionSQLGenerator("duckdb", duckdb.DialectOptions()),
+		}
+	})
+}