Este tema describe cómo consultar la información de una tabla mediante el SDK de Tablestore para Node.js.
Requisitos previos
Se requiere un cliente inicializado. Para obtener más información, consulte Initialize a Tablestore client.
Descripción del método
describeTable: function describeTable(params, callback)Código de ejemplo
A continuación se muestra un código de ejemplo que demuestra cómo consultar la información de la tabla test_table.
var params = {
tableName: 'test_table'
};
client.describeTable(params, function (err, data) {
if (err) {
console.error('error:', err);
return;
}
// Query the schema information of a table.
var tableMeta = data.tableMeta;
console.log('* Table name:', tableMeta.tableName);
console.log('* Primary key information (primary key type 1:INTEGER,2:STRING,3:BINARY)');
tableMeta.primaryKey.forEach(function (primaryKey) {
console.log(primaryKey.name, ':', primaryKey.type);
});
console.log("* Predefined column information (predefined column type 1:INTEGER,2:DOUBLE,3:BOOLEAN,4:STRING)");
tableMeta.definedColumn.forEach(function (definedColumn) {
console.log(definedColumn.name, ':', definedColumn.type);
});
// Obtain table configuration information.
var tableOptions = data.tableOptions;
console.log("* Table configuration information");
console.log("Max versions:", tableOptions.maxVersions);
console.log("Time to live:", tableOptions.timeToLive);
console.log("Max version offset:", tableOptions.deviationCellVersionInSec.toNumber());
console.log("Allow update:", tableOptions.allowUpdate);
// Obtain table Stream information.
var streamDetails = data.streamDetails
console.log("* Whether to enable Stream:", streamDetails.enableStream);
if (streamDetails.enableStream) {
console.log("Stream expiration time:", streamDetails.expirationTime);
}
// Obtain reserved read/write throughput of the table.
var reservedThroughputDetails = data.reservedThroughputDetails
console.log("* Reserved read/write throughput");
console.log("Reserved read throughput:", reservedThroughputDetails.capacityUnit.read);
console.log("Reserved write throughput:", reservedThroughputDetails.capacityUnit.write);
// Obtain secondary index information.
data.indexMetas.forEach(function (indexMeta) {
console.log("* Secondary index name:", indexMeta.name);
console.log("Primary key columns:", indexMeta.primaryKey);
console.log("Predefined columns:", indexMeta.definedColumn);
console.log("Secondary index type:", indexMeta.indexType, "(0:IT_GLOBAL_INDEX,1:IT_LOCAL_INDEX)");
console.log("Secondary index update mode:", indexMeta.indexUpdateMode, "(0:IUM_ASYNC_INDEX,1:IUM_SYNC_INDEX)");
});
});