[英]Node.js + OracleDb - Insert the last date many times
我收到了這個 JSON：
{
"TOTAL_RECORDS": 1029,
"REGISTROS": [
{
"CODIGO": "1",
"ATENDIMENTO": "1",
"PAGAMENTO": "1",
"VENCIMENTO": "2016-12-17 00:00:00",
"PROCESSAMENTO": "2016-12-10 00:00:00",
"VALOR": "1800.00000",
"NOSSO_NUMERO": "xxxxxxx",
"NUMERO_DOCUMENTO": "xxxxx",
"CODIGO_BANCO": "123",
"LINHA_DIGITAVEL": "XXX70110000180000",
"CODIGO_BARRAS": "XXX90940"
},
{
"CODIGO": "2",
"ATENDIMENTO": "2",
"PAGAMENTO": "2",
"VENCIMENTO": "2016-12-17 00:00:00",
"PROCESSAMENTO": "2016-12-10 00:00:00",
"VALOR": "2700.00000",
"NOSSO_NUMERO": "xxxxxxx",
"NUMERO_DOCUMENTO": "xxxxx",
"CODIGO_BANCO": "123",
"LINHA_DIGITAVEL": "XXX70110000180000",
"CODIGO_BARRAS": "XXX90940"
},...
然后我需要捕捉這個信息並保存在 DB Oracle 中，所以我這樣做：
module.exports = function (object, callback) {
var oracledb = require('oracledb');
for(const prop in object['REGISTROS']){
codigo = object['REGISTROS'][prop]['CODIGO'];
atendimento = object['REGISTROS'][prop]['ATENDIMENTO'];
pagamento = object['REGISTROS'][prop]['PAGAMENTO'];
vencimento = object['REGISTROS'][prop]['VENCIMENTO'];
processamento = object['REGISTROS'][prop]['PROCESSAMENTO'];
valor = parseInt(object['REGISTROS'][prop]['VALOR']);
nossoNumero = object['REGISTROS'][prop]['NOSSO_NUMERO'];
numeroDocumento = object['REGISTROS'][prop]['NUMERO_DOCUMENTO'];
codigoBanco = object['REGISTROS'][prop]['CODIGO_BANCO'];
linhaDigitavel = object['REGISTROS'][prop]['LINHA_DIGITAVEL'];
codigoBarras = object['REGISTROS'][prop]['CODIGO_BARRAS'];
oracledb.getConnection({
user: "x",
password:"xxx",
connectString: "mycon/string"
},
function(err, connection){
if (err){
console.error(err.message);
return;
}
connection.execute(
"INSERT INTO USU_TBOLETO VALUES (:USU_CODIGO, :USU_ATEND, :USU_PAGAMENTO, " +
":USU_VENCIMENTO, :USU_PROCESSA, :USU_VALOR, :USU_NOSSONUM, :NUMERODOC, :USU_CODBANCO, " +
":USU_LINHADIG , :USU_CODBARRAS)",
[codigo, atendimento, pagamento, vencimento, processamento, valor, nossoNumero,
numeroDocumento, codigoBanco, linhaDigitavel, codigoBarras],
{ autoCommit: true},
function(err, result){
if (err){
console.error(err.message);
doRelease(connection);
return;
}
console.log(codigo + ' - ' + atendimento + ' - ' + pagamento + ' - ' + vencimento);
///console.log(result.metaData);
///console.log(result.rows);
doRelease(connection);
});
});
}
function doRelease(connection) {
connection.release(
function(err){
if (err) { console.error(err.message); }
}
);
}
}
問題是它只插入了我的數據庫中的最后一條記錄，1029 次，就像總記錄一樣。 為什么？ 我不明白為什么。 INSERT 代碼在 FOR 條件中。
正確的是插入 1029 次，從 codigo 1 開始直到 1029。
阿特。 迪奧戈
當您按照當前的結構運行代碼時，它將向 libuv 的工作隊列發送許多異步操作，並且您的 JavaScript 代碼將失去控制。 我建議使用async 模塊的 eachSeries 方法來維護控制或承諾鏈（或 Node.js 7.6+ 中的 async/await）。
此外，為循環的每次迭代獲取一個新連接會大大減慢速度！ 此操作只需要一個連接。 您應該獲取連接，處理數據，關閉連接。
另一件需要重新考慮的事情是使用 autoCommit: true。 如果您對每一行都這樣做，那么您將每個插入都視為自己的事務。 如果失敗發生在中途，找出問題所在並修復它（插入剩余的行）將是困難和手動的。 我建議在插入所有內容后在連接對象上使用 commit 方法（或在循環的最后一次迭代中使用 autoCommit: true ）。
下面是一個例子：
const oracledb = require('oracledb');
const config = require('./dbConfig.js');
module.exports = function(object, callback) {
let conn;
function insertRegistro(registro, commit) {
if (commit) {
console.log('Last iteration of the loop, committing with this one');
}
return conn.execute(
`insert into usu_tboleto (
usu_codigo, usu_atend, usu_pagamento, usu_vencimento, usu_processa, usu_valor,
usu_nossonum, numerodoc, usu_codbanco, usu_linhadig, usu_codbarras
) values (
:usu_codigo, :usu_atend, :usu_pagamento, :usu_vencimento, :usu_processa, :usu_valor,
:usu_nossonum, :numerodoc, :usu_codbanco, :usu_linhadig , :usu_codbarras
)`,
{
usu_codigo: registro.CODIGO,
usu_atend: registro.ATENDIMENTO,
usu_pagamento: registro.PAGAMENTO,
usu_vencimento: registro.VENCIMENTO,
usu_processa: registro.PROCESSAMENTO,
usu_valor: registro.VALOR,
usu_nossonum: registro.NOSSO_NUMERO,
numerodoc: registro.NUMERO_DOCUMENTO,
usu_codbanco: registro.CODIGO_BANCO,
usu_linhadig: registro.LINHA_DIGITAVEL,
usu_codbarras: registro.CODIGO_BARRAS
},
{
autoCommit: commit
}
);
}
oracledb.getConnection(config)
.then(function(c) {
conn = c;
console.log('Got connection, starting loop');
let promiseChain = Promise.resolve();
object['REGISTROS'].forEach(function(registro, index) {
promiseChain = promiseChain
.then(function() {
return insertRegistro(registro, object['REGISTROS'].length === index + 1);
});
});
return promiseChain;
})
.catch(function(err) {
console.log(err);
console.log('Encountered error, rolling back transaction');
return conn.rollback()
.then(function() {
console.log('Transaction rolled back');
})
.catch(function(err) {
console.log('Error rolling back', err);
});
})
.then(function() {
return conn.close();
})
.then(function() {
console.log('Connection closed');
})
.catch(function(err) {
console.log(err);
});
}
您可以通過將往返次數從 1029 次減少到 1 次（一次執行所有操作）或 3 次（如果一次執行 500 組）來進一步優化。 這將大大提高性能。 這是一個以 500 為一組進行批量插入的示例。
const oracledb = require('oracledb');
const config = require('./dbConfig.js');
module.exports = function(object, callback) {
let conn;
function insertRegistros(opts) {
if (opts.commit) {
console.log('Last iteration of the loop, committing with this one');
}
return conn.execute(
`declare
type varchar2_aat is table of varchar2(50)
index by pls_integer;
l_usu_codigo_vals varchar2_aat;
begin
l_usu_codigo_vals := :usu_codigo_vals;
forall x in 1 .. l_usu_codigo_vals.count
insert into usu_tboleto (
usu_codigo, usu_atend, usu_pagamento, usu_vencimento, usu_processa, usu_valor,
usu_nossonum, numerodoc, usu_codbanco, usu_linhadig, usu_codbarras
) values (
:usu_codigo_vals(x), :usu_atend_vals(x), :usu_pagamento_vals(x), :usu_vencimento_vals(x), :usu_processa_vals(x), :usu_valor_vals(x),
:usu_nossonum_vals(x), :numerodoc_vals(x), :usu_codbanco_vals(x), :usu_linhadig_vals(x) , :usu_codbarras_vals(x)
);
end;`,
{
usu_codigo_vals: {type: oracledb.STRING, dir: oracledb.BIND_IN, val: opts.usu_codigo_vals},
usu_atend_vals: {type: oracledb.STRING, dir: oracledb.BIND_IN, val: opts.usu_atend_vals},
usu_pagamento_vals: {type: oracledb.STRING, dir: oracledb.BIND_IN, val: opts.usu_pagamento_vals},
usu_vencimento_vals: {type: oracledb.STRING, dir: oracledb.BIND_IN, val: opts.usu_vencimento_vals},
usu_processa_vals: {type: oracledb.STRING, dir: oracledb.BIND_IN, val: opts.usu_processa_vals},
usu_valor_vals: {type: oracledb.STRING, dir: oracledb.BIND_IN, val: opts.usu_valor_vals},
usu_nossonum_vals: {type: oracledb.STRING, dir: oracledb.BIND_IN, val: opts.usu_nossonum_vals},
numerodoc_vals: {type: oracledb.STRING, dir: oracledb.BIND_IN, val: opts.numerodoc_vals},
usu_codbanco_vals: {type: oracledb.STRING, dir: oracledb.BIND_IN, val: opts.usu_codbanco_vals},
usu_linhadig_vals: {type: oracledb.STRING, dir: oracledb.BIND_IN, val: opts.usu_linhadig_vals},
usu_codbarras_vals: {type: oracledb.STRING, dir: oracledb.BIND_IN, val: opts.usu_codbarras_vals}
},
{
autoCommit: opts.commit
}
);
}
oracledb.getConnection(config)
.then(function(c) {
conn = c;
console.log('Got connection, starting loop');
const batchRowCount = 500;
const loops = Math.ceil(object['REGISTROS'].length / batchRowCount);
let promiseChain = Promise.resolve();
let registrosIdx = 0;
for (let outerIndex = 0; outerIndex < loops; outerIndex += 1) {
(function() {
const usu_codigo_vals = [];
const usu_atend_vals = [];
const usu_pagamento_vals = [];
const usu_vencimento_vals = [];
const usu_processa_vals = [];
const usu_valor_vals = [];
const usu_nossonum_vals = [];
const numerodoc_vals = [];
const usu_codbanco_vals = [];
const usu_linhadig_vals = [];
const usu_codbarras_vals = [];
for (let idx = 0; idx < batchRowCount; idx += 1) {
if (registrosIdx === object['REGISTROS'].length) {
break;
}
usu_codigo_vals.push(object['REGISTROS'][registrosIdx].CODIGO);
usu_atend_vals.push(object['REGISTROS'][registrosIdx].ATENDIMENTO);
usu_pagamento_vals.push(object['REGISTROS'][registrosIdx].PAGAMENTO);
usu_vencimento_vals.push(object['REGISTROS'][registrosIdx].VENCIMENTO);
usu_processa_vals.push(object['REGISTROS'][registrosIdx].PROCESSAMENTO);
usu_valor_vals.push(object['REGISTROS'][registrosIdx].VALOR);
usu_nossonum_vals.push(object['REGISTROS'][registrosIdx].NOSSO_NUMERO);
numerodoc_vals.push(object['REGISTROS'][registrosIdx].NUMERO_DOCUMENTO);
usu_codbanco_vals.push(object['REGISTROS'][registrosIdx].CODIGO_BANCO);
usu_linhadig_vals.push(object['REGISTROS'][registrosIdx].LINHA_DIGITAVEL);
usu_codbarras_vals.push(object['REGISTROS'][registrosIdx].CODIGO_BARRAS);
registrosIdx += 1;
}
promiseChain = promiseChain
.then(function() {
return insertRegistros({
usu_codigo_vals: usu_codigo_vals,
usu_atend_vals: usu_atend_vals,
usu_pagamento_vals: usu_pagamento_vals,
usu_vencimento_vals: usu_vencimento_vals,
usu_processa_vals: usu_processa_vals,
usu_valor_vals: usu_valor_vals,
usu_nossonum_vals: usu_nossonum_vals,
numerodoc_vals: numerodoc_vals,
usu_codbanco_vals: usu_codbanco_vals,
usu_linhadig_vals: usu_linhadig_vals,
usu_codbarras_vals: usu_codbarras_vals,
commit: outerIndex + 1 === loops
});
});
})();
}
return promiseChain;
})
.catch(function(err) {
console.log(err);
console.log('Encountered error, rolling back transaction');
return conn.rollback()
.then(function() {
console.log('Transaction rolled back');
})
.catch(function(err) {
console.log('Error rolling back', err);
});
})
.then(function() {
return conn.close();
})
.then(function() {
console.log('Connection closed');
})
.catch(function(err) {
console.log(err);
});
}
如您所見，代碼變得有點棘手。 但是，當驅動程序添加對綁定記錄數組的支持而不僅僅是字符串或數字時，這在將來會變得更簡單。
你可以在這里閱讀更多關於我在我的博客上使用的工作： https : //jsao.io/2017/01/plsql-record-types-and-the-node-js-driver/
for循環幾乎立即執行，而數據庫操作是異步且緩慢的。 for循環必須在異步操作的回調執行時完成，因此它只會在循環的最后一次迭代期間看到值。
為了避免這種情況，您可以使用 ES6 的const聲明變量，這將創建塊作用域變量。 將您的代碼更改為此，它應該可以工作：
module.exports = function(object, callback) {
var oracledb = require('oracledb');
for (const prop in object['REGISTROS']) {
const codigo = object['REGISTROS'][prop]['CODIGO'];
const atendimento = object['REGISTROS'][prop]['ATENDIMENTO'];
const pagamento = object['REGISTROS'][prop]['PAGAMENTO'];
const vencimento = object['REGISTROS'][prop]['VENCIMENTO'];
const processamento = object['REGISTROS'][prop]['PROCESSAMENTO'];
const valor = parseInt(object['REGISTROS'][prop]['VALOR']);
const nossoNumero = object['REGISTROS'][prop]['NOSSO_NUMERO'];
const numeroDocumento = object['REGISTROS'][prop]['NUMERO_DOCUMENTO'];
const codigoBanco = object['REGISTROS'][prop]['CODIGO_BANCO'];
const linhaDigitavel = object['REGISTROS'][prop]['LINHA_DIGITAVEL'];
const codigoBarras = object['REGISTROS'][prop]['CODIGO_BARRAS'];
oracledb.getConnection({
user: "x",
password: "xxx",
connectString: "mycon/string"
},
function(err, connection) {
if (err) {
console.error(err.message);
return;
}
connection.execute(
"INSERT INTO USU_TBOLETO VALUES (:USU_CODIGO, :USU_ATEND, :USU_PAGAMENTO, " +
":USU_VENCIMENTO, :USU_PROCESSA, :USU_VALOR, :USU_NOSSONUM, :NUMERODOC, :USU_CODBANCO, " +
":USU_LINHADIG , :USU_CODBARRAS)",
[codigo, atendimento, pagamento, vencimento, processamento, valor, nossoNumero,
numeroDocumento, codigoBanco, linhaDigitavel, codigoBarras
], {
autoCommit: true
},
function(err, result) {
if (err) {
console.error(err.message);
doRelease(connection);
return;
}
console.log(codigo + ' - ' + atendimento + ' - ' + pagamento + ' - ' + vencimento);
///console.log(result.metaData);
///console.log(result.rows);
doRelease(connection);
});
});
}
function doRelease(connection) {
connection.release(
function(err) {
if (err) {
console.error(err.message);
}
}
);
}
}
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