github.com/insionng/yougam@v0.0.0-20170714101924-2bc18d833463/libraries/go-xorm/xorm/rows.go (about)

     1  // Copyright 2015 The Xorm Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package xorm
     6  
     7  import (
     8  	"database/sql"
     9  	"fmt"
    10  	"reflect"
    11  
    12  	"github.com/insionng/yougam/libraries/go-xorm/core"
    13  )
    14  
    15  // Rows rows wrapper a rows to
    16  type Rows struct {
    17  	NoTypeCheck bool
    18  
    19  	session     *Session
    20  	stmt        *core.Stmt
    21  	rows        *core.Rows
    22  	fields      []string
    23  	fieldsCount int
    24  	beanType    reflect.Type
    25  	lastError   error
    26  }
    27  
    28  func newRows(session *Session, bean interface{}) (*Rows, error) {
    29  	rows := new(Rows)
    30  	rows.session = session
    31  	rows.beanType = reflect.Indirect(reflect.ValueOf(bean)).Type()
    32  
    33  	defer rows.session.resetStatement()
    34  
    35  	var sqlStr string
    36  	var args []interface{}
    37  
    38  	rows.session.Statement.setRefValue(rValue(bean))
    39  	if len(session.Statement.TableName()) <= 0 {
    40  		return nil, ErrTableNotFound
    41  	}
    42  
    43  	if rows.session.Statement.RawSQL == "" {
    44  		sqlStr, args = rows.session.Statement.genGetSQL(bean)
    45  	} else {
    46  		sqlStr = rows.session.Statement.RawSQL
    47  		args = rows.session.Statement.RawParams
    48  	}
    49  
    50  	for _, filter := range rows.session.Engine.dialect.Filters() {
    51  		sqlStr = filter.Do(sqlStr, session.Engine.dialect, rows.session.Statement.RefTable)
    52  	}
    53  
    54  	rows.session.saveLastSQL(sqlStr, args...)
    55  	var err error
    56  	if rows.session.prepareStmt {
    57  		rows.stmt, err = rows.session.DB().Prepare(sqlStr)
    58  		if err != nil {
    59  			rows.lastError = err
    60  			rows.Close()
    61  			return nil, err
    62  		}
    63  
    64  		rows.rows, err = rows.stmt.Query(args...)
    65  		if err != nil {
    66  			rows.lastError = err
    67  			rows.Close()
    68  			return nil, err
    69  		}
    70  	} else {
    71  		rows.rows, err = rows.session.DB().Query(sqlStr, args...)
    72  		if err != nil {
    73  			rows.lastError = err
    74  			rows.Close()
    75  			return nil, err
    76  		}
    77  	}
    78  
    79  	rows.fields, err = rows.rows.Columns()
    80  	if err != nil {
    81  		rows.lastError = err
    82  		rows.Close()
    83  		return nil, err
    84  	}
    85  	rows.fieldsCount = len(rows.fields)
    86  
    87  	return rows, nil
    88  }
    89  
    90  // Next move cursor to next record, return false if end has reached
    91  func (rows *Rows) Next() bool {
    92  	if rows.lastError == nil && rows.rows != nil {
    93  		hasNext := rows.rows.Next()
    94  		if !hasNext {
    95  			rows.lastError = sql.ErrNoRows
    96  		}
    97  		return hasNext
    98  	}
    99  	return false
   100  }
   101  
   102  // Err returns the error, if any, that was encountered during iteration. Err may be called after an explicit or implicit Close.
   103  func (rows *Rows) Err() error {
   104  	return rows.lastError
   105  }
   106  
   107  // Scan row record to bean properties
   108  func (rows *Rows) Scan(bean interface{}) error {
   109  	if rows.lastError != nil {
   110  		return rows.lastError
   111  	}
   112  
   113  	if !rows.NoTypeCheck && reflect.Indirect(reflect.ValueOf(bean)).Type() != rows.beanType {
   114  		return fmt.Errorf("scan arg is incompatible type to [%v]", rows.beanType)
   115  	}
   116  
   117  	return rows.session.row2Bean(rows.rows, rows.fields, rows.fieldsCount, bean)
   118  }
   119  
   120  // Close session if session.IsAutoClose is true, and claimed any opened resources
   121  func (rows *Rows) Close() error {
   122  	if rows.session.IsAutoClose {
   123  		defer rows.session.Close()
   124  	}
   125  
   126  	if rows.lastError == nil {
   127  		if rows.rows != nil {
   128  			rows.lastError = rows.rows.Close()
   129  			if rows.lastError != nil {
   130  				defer rows.stmt.Close()
   131  				return rows.lastError
   132  			}
   133  		}
   134  		if rows.stmt != nil {
   135  			rows.lastError = rows.stmt.Close()
   136  		}
   137  	} else {
   138  		if rows.stmt != nil {
   139  			defer rows.stmt.Close()
   140  		}
   141  		if rows.rows != nil {
   142  			defer rows.rows.Close()
   143  		}
   144  	}
   145  	return rows.lastError
   146  }