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Lu, Huayi e6fa411af0 DWS DEV 830.201 version 
Reviewed-by: Pruthi, Vineet <vineet.pruthi@t-systems.com>
Co-authored-by: Lu, Huayi <luhuayi@huawei.com>
Co-committed-by: Lu, Huayi <luhuayi@huawei.com>
2024-05-16 07:24:04 +00:00

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<a name="EN-US_TOPIC_0000001188323684"></a><a name="EN-US_TOPIC_0000001188323684"></a>
<h1 class="topictitle1">Parallel OBS Data Export</h1>
<div id="body8662426"><div class="section" id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_sb2ed2abd32a94d3896b3f07d1fe05b91"><h4 class="sectiontitle">Overview</h4><div class="p" id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_aada6c8c93f034e448e74e106ef84c8a4"><span id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_ph1692512422530">GaussDB(DWS)</span> databases allow you to export data in parallel using OBS foreign tables, in which the export mode and the exported data format are specified. Data is exported in parallel through multiple DNs from <span id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_ph325516531162">GaussDB(DWS)</span> to the OBS server, improving the overall export performance.<ul id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_u8cb2994a33d84a4587e0a4ed60c9219f"><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_l31f934f062fc4d73bb806420f4e0ab2a">The CN only plans data export tasks and delivers the tasks to DNs for execution. In this case, the CN is released to process external requests.</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_ldd50fb5c0ad54fe6834d26dfefb17575">Every DN is involved in data export, and the computing capabilities and bandwidths of all the DNs are fully leveraged to export data.</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_li12576017209">You can concurrently export data using multiple OBS services, but the bucket and object paths specified for the export tasks must be different and cannot be null.</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_li1659182513013">The OBS server connects to GaussDB(DWS) cluster nodes. The export rate is affected by the network bandwidth.</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_li529717211107">The TEXT and CSV data file formats are supported. The size of data in a single row must be less than 1 GB.</li><li id="EN-US_TOPIC_0000001188323684__li1411511407471">Data in ORC format is supported only by 8.1.0 or later.</li><li id="EN-US_TOPIC_0000001188323684__li943792653319">To ensure the correctness of data import or export, you need to import or export data from OBS in the same compatibility mode.<p id="EN-US_TOPIC_0000001188323684__p19186102919338"><a name="EN-US_TOPIC_0000001188323684__li943792653319"></a><a name="li943792653319"></a>For example, data imported or exported in MySQL compatibility mode can be exported or imported only in MySQL compatibility mode.</p>
</li></ul>
</div>
</div>
<div class="section" id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_s76f58320ec2049cca8f61b6f9310a0b8"><h4 class="sectiontitle">Related Concepts</h4><ul id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_u3b90148024b347319c44296cecdc9f18"><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_li148159103246"><strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_b40899401103246">Source data file</strong>: a TEXT or CSV file that stores data.</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_l144b275bcfef4133b5e2b0ee84749707"><strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_a9a8934a5fa144e38b570905d79c7f385">OBS</strong>: a cloud storage service used to store unstructured data, such as documents, images, and videos. Data objects concurrently exported from <span id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_ph10680613174">GaussDB(DWS)</span> are stored on the OBS server.</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_l331e0761386349b9947093320b8a7994"><strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_a33279fac75964c80b0c5210e9b07ff7a">Bucket</strong>: a container storing objects on OBS.<ul id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_u36bc73d8d2f44c74a97c80e8b83987bd"><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_l55b1bd39af0f4bbfa400d7b50ed795d8">Object storage is a flat storage mode. Layered file system structures are not needed because all objects in buckets are at the same logical layer.</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_le04bb26a4407473fac3047e3506e12c0">In OBS, each bucket name must be unique and cannot be changed. A default access control list (ACL) is created with a bucket. Each item in the ACL contains permissions granted to certain users, such as <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b3798956114420">READ</strong>, <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b979820563447">WRITE</strong>, and <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b1879875610442">FULL_CONTROL</strong>. Only authorized users can perform bucket operations, such as creating, deleting, viewing, and setting ACLs for buckets.</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_ledfd08dfba934ae79119138b124c1a41">A user can create a maximum of 100 buckets. The total data size and the number of objects and files in each bucket are not limited.</li></ul>
</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_l8061dcd1e4984bd2b5e246447e965074"><strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_a3441f1e250554c25aab081fd1dfe5d98">Object</strong>: a basic data storage unit in OBS. Data uploaded by users is stored in OBS buckets as objects. Object attributes include <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b10801256134417">Key</strong>, <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b1080118562441">Metadata</strong>, and <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b0801556194415">Data</strong>.<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_en-us_topic_0102849790_p918400115144">Generally, objects are managed as files. However, OBS has no file system–related concepts, such as files or folders. To let users easily manage data, OBS allows them to simulate folders. Users can add a slash (/) in the object name, for example, <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b58030567445">tpcds1000/stock.csv</strong>. In this name, <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b580318566448">tpcds1000</strong> is regarded as the folder name and <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b88031556164418">stock.csv</strong> the file name. The value of <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b08031656134414">key</strong> (object name) is still <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b5803105620444">tpcds1000/stock.csv</strong>, and the content of the object is the content of the <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b18031156174412">stock.csv</strong> file.</p>
</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_labd5e1beb0f749ecb462f6a5da04ec90"><strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b1380514562442">Key</strong>: name of an object. It is a UTF-8 character sequence containing 1 to 1024 characters. A key value must be unique in a bucket. Users can name the objects they stored or obtained as <em id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_i1580555615440">Bucket name</em><strong id="EN-US_TOPIC_0000001188323684__b1726928174213">+</strong><em id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_i68056564442">Object name</em>.</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_l49ab78452d15405cb44e1c4bf69416b6"><strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_ac5b9dbbd842f4fe4b217a6314dfda411">Metadata</strong>: object metadata, which contains information about the object. There are system metadata and user metadata. The metadata is uploaded to OBS as key-value pairs together with HTTP headers.<ul id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_u46b9049023414ed58f61bf378c30ab07"><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_l8c1eefbf5d9a4d4b9ab3bcc2f6306b3a">System metadata is generated by OBS and used for processing object data. System metadata includes <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b11809165614414">Date</strong>, <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b480925610442">Content-length</strong>, <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b1810156184413">last-modify</strong>, and <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b6810175624413">Content-MD5</strong>.</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_lfa7d499b7c1342d6b0d3392aaa2ee0c4">User metadata contains object descriptions specified by users for uploading objects.</li></ul>
</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_lc7e1c47f95dd46e08f24859c44d74fe2"><strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_af1c484d05d894f6ba9872f5f8d3248f0">Data</strong>: object content, which is regarded by OBS as stateless binary data.</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_lfb4fbedc76974168853131769719dc1d"><strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407664_a21d6d69fd0204c30a9387ccbf19f9745">Foreign table</strong>: A foreign table is used to identify data in a source data file. It stores information, such as the location, format, destination location, encoding format, and data delimiter of a source data file.</li></ul>
</div>
<div class="section" id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_s8a6e529209bf43c090824b3e8523a546"><h4 class="sectiontitle">Principles</h4><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_aa52a1e73d430457c879a6bfd5ba1c89c">The following describes the principles of exporting data from a cluster to OBS by using a distributed hash table or a replication table.</p>
<ul id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_ufbf538ea1435428e9e64aace075cf3d0"><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_la084220b1176437381a5219de8311e5d">Distributed hash table: the table for which <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b39871841131016">DISTRIBUTE BY HASH (Column_Name)</strong> is specified in the table creation statement.<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_a40bd621ef3764ee8b1a92b5b9f525f71">A distributed hash table stores data in hash mode. <a href="#EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_f3c36ca500176469491e1a5942e1f1722">Figure 1</a> shows how to export data from table (<strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b84235270615952">T2</strong>) to OBS as an example.</p>
<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_a517072c1a00a4772b921533ce701e65d">During table data storage, the <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b16234057131017">col2</strong> hash column in table <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b3235115716104">T2</strong> is hashed, and a hash value is generated. The tuple is distributed to corresponding DNs for storage according to the mapping between the DNs and the hash value.</p>
<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_a76ca24cd44454dbfbdef2358ad801b45">When data is exported to OBS, DNs that store the exported data of <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b1145933121114">T2</strong> directly export their data files to OBS. Original data on multiple nodes will be exported in parallel.</p>
<div class="fignone" id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_f3c36ca500176469491e1a5942e1f1722"><a name="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_f3c36ca500176469491e1a5942e1f1722"></a><a name="en-us_topic_0000001145491123_f3c36ca500176469491e1a5942e1f1722"></a><span class="figcap"><b>Figure 1 </b>Hash distribution principle</span><br><span><img class="vsd" id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_image996914117545" src="figure/en-us_image_0000001233681871.png"></span></div>
</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_l9f730b2e51914d67805a7fda12e67468">Replication table: the table for which <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b88334145471">DISTRIBUTE BY REPLICATION</strong> is specified in the table creation statement.<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_a451dd6e807e24199b148ebbf477b9f62">A replication table stores a package of complete table data on each <span id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_ph7156016194">GaussDB(DWS)</span> node. When exporting data to OBS, <span id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_ph246193519231">GaussDB(DWS)</span> randomly selects a DN for export.</p>
</li></ul>
</div>
<div class="section" id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_sd7122712049c4f66862fd1c4f938fa6e"><h4 class="sectiontitle">Naming Rules of Exported Files</h4><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_a66fb5ed0a10948f39e713e7ca66b1fca">Rules for naming the files exported from <span id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_ph623521051917">GaussDB(DWS)</span> to OBS are as follows:</p>
<ul id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_ucf68569f5b2f4463b768ce30ace72931"><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_lda2e546a1a55419186c0cfff628e6782">Data exported from DNs is stored on OBS in segment format. The file is named as <em id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_i1281116515163">Table name</em><strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b15811105191611">_</strong><em id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_i9813135181619">Node name</em><strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b1814195161616">_segment.</strong><em id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_i1981475111617">n</em>. <em id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_i583615619444">n</em> is a natural number starting from 0, for example, 0, 1, 2, 3.<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_a9c7936ba481c4a99a956d7d46c7e1090">For example, the data of table <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b684035617443">t1</strong> on <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b2841456164417">datanode3</strong> will be exported as <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b1784125610449">t1_datanode3_segment.0</strong>, <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b108411156144412">t1_datanode3_segment.1</strong>, and so on.</p>
<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0093837405_p939450710194">You are advised to export data from different clusters or databases to different OBS buckets or different paths of the same OBS bucket.</p>
</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_l4c9fcebbb65b4e79a22e73a34dc9fc07">Each segment can store a maximum of 1 GB data, with no tuples sliced. If data stored in a segment exceeds 1 GB, the excess data will be stored in the second segment.<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_aec1eb7e05fa24da5a4be5408f4883137"><a name="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_l4c9fcebbb65b4e79a22e73a34dc9fc07"></a><a name="en-us_topic_0000001145491123_l4c9fcebbb65b4e79a22e73a34dc9fc07"></a>For example:</p>
<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_af0992aae9fea4ac9abb79a728f16ef3d">A segment has already stored 100 pieces of tuples (1023 MB) when <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b685095614449">datanode3</strong> exports data from <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b98507569449">t1</strong> to OBS. If a 5 MB tuple is inserted to the segment, the data size becomes 1028 MB. In this case, file <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b1185018563443">t1_datanode3_segment.0</strong> (1023 MB) is generated and stored on OBS, and the new tuple is stored on OBS as file <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_b9850125617440">t1_datanode3_segment.1</strong>.</p>
</li><li id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_l5c84571404f2477f87dca78819acd73d">When data is exported from a distributed hash table, the number of segments generated on each DN depends on the data volume stored on a DN, not on the number of DNs in the cluster. Data stored in hash mode may not be evenly distributed on each DN.<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0093837405_p352520135314"><a name="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_l5c84571404f2477f87dca78819acd73d"></a><a name="en-us_topic_0000001145491123_l5c84571404f2477f87dca78819acd73d"></a>For example, a cluster has <strong id="EN-US_TOPIC_0000001188323684__b20192134918213">DataNode1</strong>, <strong id="EN-US_TOPIC_0000001188323684__b831245213213">DataNode2</strong>, <strong id="EN-US_TOPIC_0000001188323684__b392014542211">DataNode3</strong>, <strong id="EN-US_TOPIC_0000001188323684__b127142571225">DataNode4</strong>, <strong id="EN-US_TOPIC_0000001188323684__b611315010314">DataNode5</strong>, and <strong id="EN-US_TOPIC_0000001188323684__b166841721337">DataNode6</strong>, which store 1.5 GB, 0.7 GB, 0.6 GB, 0.8 GB, 0.4 GB, and 0.5 GB data, respectively. Seven OBS segment files will be generated during data export because <strong id="EN-US_TOPIC_0000001188323684__b182412111335">DataNode1</strong> will generate two segment files, which store 1 GB and 0.5 GB data, respectively.</p>
</li></ul>
</div>
<div class="section" id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_s2b14d3d85d5741a5bd6ff1c3383c38f2"><h4 class="sectiontitle">Data Export Process</h4><div class="fignone" id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_fig61780939163452"><span class="figcap"><b>Figure 2 </b>Concurrent data export</span><br><span><img class="vsd" id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_image1633118373111" src="figure/en-us_image_0000001233563381.png"></span></div>
<div class="tablenoborder"><table cellpadding="4" cellspacing="0" summary="" id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_t43fc24262f6b40cca88d4633efd0e5c7" frame="border" border="1" rules="all"><caption><b>Table 1 </b>Process description</caption><thead align="left"><tr id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_r2947856e4c75478c9ef12f5df77200b2"><th align="left" class="cellrowborder" valign="top" width="19.99%" id="mcps1.3.5.3.2.4.1.1"><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_a077931f99fba42fba9ba64990f2635ee">Procedure</p>
</th>
<th align="left" class="cellrowborder" valign="top" width="38.97%" id="mcps1.3.5.3.2.4.1.2"><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_a3a1ed88672ae47fabc73eb3cee95fb85">Description</p>
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<th align="left" class="cellrowborder" valign="top" width="41.04%" id="mcps1.3.5.3.2.4.1.3"><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_a122c4c71d3de42ee8dfd191f05fef05f">Subtask</p>
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</thead>
<tbody><tr id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_r0003afc325134c0da6544ae550d35e80"><td class="cellrowborder" valign="top" width="19.99%" headers="mcps1.3.5.3.2.4.1.1 "><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_a9bea9dc707754a90aaa27c20905e75a2">Plan data export.</p>
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<td class="cellrowborder" valign="top" width="38.97%" headers="mcps1.3.5.3.2.4.1.2 "><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_ac888c13c344f4dc380c1a3d0dc569a3a">Create an OBS bucket and a folder in the OBS bucket as the directory for storing exported data files.</p>
<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_p52968220102122">For details, see <a href="dws_04_0252.html">Planning Data Export</a>.</p>
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<td class="cellrowborder" valign="top" width="41.04%" headers="mcps1.3.5.3.2.4.1.3 "><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_a2b7ae7e79332421bbb0eb4411542d22c">-</p>
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<tr id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_r8b235ba88ec74d9e99c5624c3777cc39"><td class="cellrowborder" valign="top" width="19.99%" headers="mcps1.3.5.3.2.4.1.1 "><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_a8fc870885fcc4f5384a3a7e9a075436f">Create an OBS foreign table.</p>
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<td class="cellrowborder" valign="top" width="38.97%" headers="mcps1.3.5.3.2.4.1.2 "><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_a498a4d797ddf4971a89ba5c739aa4fee">Create a foreign table to help OBS specify information about data files to be exported. The foreign table stores information, such as the destination location, format, encoding, and data delimiter of a source data file.</p>
<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_p168301738204117">For details, see <a href="dws_04_0253.html">Creating an OBS Foreign Table</a>.</p>
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<td class="cellrowborder" valign="top" width="41.04%" headers="mcps1.3.5.3.2.4.1.3 "><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_p1859016717436">-</p>
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<tr id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_r93734627829048eab3b6a48132ce2fc3"><td class="cellrowborder" valign="top" width="19.99%" headers="mcps1.3.5.3.2.4.1.1 "><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_a2f25dc2ff6ff4d25ba3b36dc294d6f92">Export data.</p>
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<td class="cellrowborder" valign="top" width="38.97%" headers="mcps1.3.5.3.2.4.1.2 "><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_a8c77d6d5e8e84a7d9263f991cc519812">After the foreign table is created, run the <strong id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0085031809_b842352706163840">INSERT</strong> statement to efficiently export data to data files.</p>
<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_p578110413424">For details, see <a href="dws_04_0254.html">Exporting Data</a>.</p>
<p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_a4873ba59f453443383ec67417e5d3d60"></p>
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<td class="cellrowborder" valign="top" width="41.04%" headers="mcps1.3.5.3.2.4.1.3 "><p id="EN-US_TOPIC_0000001188323684__en-us_topic_0000001145491123_en-us_topic_0117407657_p1390783912426">-</p>
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<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dws_04_0250.html">Exporting Data to OBS</a></div>
</div>
</div>
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