mirror of
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Refined KILL QUERY doc, add conf and Makefile for rst docs. [#CLICKHOUSE-3]
This commit is contained in:
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@ -2292,6 +2292,19 @@ You can put an asterisk in any part of a query instead of an expression. When th
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- In subqueries (since columns that aren't needed for the external query are excluded from subqueries).
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In all other cases, we don't recommend using the asterisk, since it only gives you the drawbacks of a columnar DBMS instead of the advantages.
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===KILL QUERY===
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%%KILL QUERY WHERE <where expression to SELECT FROM system.processes query> [SYNC|ASYNC|TEST] [FORMAT format]%%
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Tries to finish currently executing queries.
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Queries to be finished are selected from %%system.processes%% table according to expression after WHERE term.
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Examples:
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%%KILL QUERY WHERE query_id='2-857d-4a57-9ee0-327da5d60a90'%%
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Finishes all queries with specified %%query_id%%.
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%%KILL QUERY WHERE user='username' SYNC%%
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Synchronously finishes all queries of user %%username%%.
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Readonly users can kill only own queries.
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</div>
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<div class="island">
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@ -2328,10 +2328,17 @@ ORDER BY EventDate ASC
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===KILL QUERY===
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%%KILL QUERY WHERE expression_for_system.processes [SYNC|ASYNC|TEST] [FORMAT format]%%
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%%KILL QUERY WHERE <where expression to SELECT FROM system.processes query> [SYNC|ASYNC|TEST] [FORMAT format]%%
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Пытается завершить исполняющиеся в данный момент запросы.
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Запросы для завершения выбираются из таблицы system.processes для которых выражение expression_for_system.processes истинно.
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Запросы для завершения выбираются из таблицы %%system.processes%% для которых выражение после WHERE истинно.
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Примеры:
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%%KILL QUERY WHERE query_id='2-857d-4a57-9ee0-327da5d60a90'%%
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Завершает все запросы с указанным %%query_id%%.
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%%KILL QUERY WHERE user='username' SYNC%%
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Синхронно завершает все запросы пользователя %%username%%.
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Readonly-пользователи могут совершать только свои запросы.
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По-умолчанию используется асинхронный вариант запроса (ASYNC), который завершается не ожидая завершения запросов.
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Синхронный вариант (SYNC) ожидает завершения всех запросов и построчно выводит информацию о процессах по ходу их завершения.
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177
docs/Makefile
Normal file
177
docs/Makefile
Normal file
@ -0,0 +1,177 @@
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# Makefile for Sphinx documentation
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#
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# You can set these variables from the command line.
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SPHINXOPTS =
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SPHINXBUILD = sphinx-build
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PAPER =
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BUILDDIR = build
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# User-friendly check for sphinx-build
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ifeq ($(shell which $(SPHINXBUILD) >/dev/null 2>&1; echo $$?), 1)
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$(error The '$(SPHINXBUILD)' command was not found. Make sure you have Sphinx installed, then set the SPHINXBUILD environment variable to point to the full path of the '$(SPHINXBUILD)' executable. Alternatively you can add the directory with the executable to your PATH. If you don't have Sphinx installed, grab it from http://sphinx-doc.org/)
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endif
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# Internal variables.
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PAPEROPT_a4 = -D latex_paper_size=a4
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PAPEROPT_letter = -D latex_paper_size=letter
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ALLSPHINXOPTS = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) ru
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# the i18n builder cannot share the environment and doctrees with the others
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I18NSPHINXOPTS = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) ru
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.PHONY: help clean html dirhtml singlehtml pickle json htmlhelp qthelp devhelp epub latex latexpdf text man changes linkcheck doctest gettext
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help:
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@echo "Please use \`make <target>' where <target> is one of"
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@echo " html to make standalone HTML files"
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@echo " dirhtml to make HTML files named index.html in directories"
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@echo " singlehtml to make a single large HTML file"
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@echo " pickle to make pickle files"
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@echo " json to make JSON files"
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@echo " htmlhelp to make HTML files and a HTML help project"
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@echo " qthelp to make HTML files and a qthelp project"
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@echo " devhelp to make HTML files and a Devhelp project"
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@echo " epub to make an epub"
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@echo " latex to make LaTeX files, you can set PAPER=a4 or PAPER=letter"
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@echo " latexpdf to make LaTeX files and run them through pdflatex"
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@echo " latexpdfja to make LaTeX files and run them through platex/dvipdfmx"
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@echo " text to make text files"
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@echo " man to make manual pages"
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@echo " texinfo to make Texinfo files"
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@echo " info to make Texinfo files and run them through makeinfo"
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@echo " gettext to make PO message catalogs"
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@echo " changes to make an overview of all changed/added/deprecated items"
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@echo " xml to make Docutils-native XML files"
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@echo " pseudoxml to make pseudoxml-XML files for display purposes"
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@echo " linkcheck to check all external links for integrity"
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@echo " doctest to run all doctests embedded in the documentation (if enabled)"
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clean:
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rm -rf $(BUILDDIR)/*
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html:
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$(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html
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@echo
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@echo "Build finished. The HTML pages are in $(BUILDDIR)/html."
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dirhtml:
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$(SPHINXBUILD) -b dirhtml $(ALLSPHINXOPTS) $(BUILDDIR)/dirhtml
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@echo
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@echo "Build finished. The HTML pages are in $(BUILDDIR)/dirhtml."
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singlehtml:
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$(SPHINXBUILD) -b singlehtml $(ALLSPHINXOPTS) $(BUILDDIR)/singlehtml
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@echo
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@echo "Build finished. The HTML page is in $(BUILDDIR)/singlehtml."
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pickle:
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$(SPHINXBUILD) -b pickle $(ALLSPHINXOPTS) $(BUILDDIR)/pickle
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@echo
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@echo "Build finished; now you can process the pickle files."
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json:
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$(SPHINXBUILD) -b json $(ALLSPHINXOPTS) $(BUILDDIR)/json
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@echo
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@echo "Build finished; now you can process the JSON files."
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htmlhelp:
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$(SPHINXBUILD) -b htmlhelp $(ALLSPHINXOPTS) $(BUILDDIR)/htmlhelp
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@echo
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@echo "Build finished; now you can run HTML Help Workshop with the" \
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".hhp project file in $(BUILDDIR)/htmlhelp."
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qthelp:
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$(SPHINXBUILD) -b qthelp $(ALLSPHINXOPTS) $(BUILDDIR)/qthelp
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@echo
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@echo "Build finished; now you can run "qcollectiongenerator" with the" \
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".qhcp project file in $(BUILDDIR)/qthelp, like this:"
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@echo "# qcollectiongenerator $(BUILDDIR)/qthelp/ClickHouse.qhcp"
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@echo "To view the help file:"
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@echo "# assistant -collectionFile $(BUILDDIR)/qthelp/ClickHouse.qhc"
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devhelp:
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$(SPHINXBUILD) -b devhelp $(ALLSPHINXOPTS) $(BUILDDIR)/devhelp
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@echo
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@echo "Build finished."
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@echo "To view the help file:"
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@echo "# mkdir -p $$HOME/.local/share/devhelp/ClickHouse"
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@echo "# ln -s $(BUILDDIR)/devhelp $$HOME/.local/share/devhelp/ClickHouse"
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@echo "# devhelp"
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epub:
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$(SPHINXBUILD) -b epub $(ALLSPHINXOPTS) $(BUILDDIR)/epub
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@echo
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@echo "Build finished. The epub file is in $(BUILDDIR)/epub."
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latex:
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$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
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@echo
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@echo "Build finished; the LaTeX files are in $(BUILDDIR)/latex."
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@echo "Run \`make' in that directory to run these through (pdf)latex" \
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"(use \`make latexpdf' here to do that automatically)."
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latexpdf:
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$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
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@echo "Running LaTeX files through pdflatex..."
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$(MAKE) -C $(BUILDDIR)/latex all-pdf
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@echo "pdflatex finished; the PDF files are in $(BUILDDIR)/latex."
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latexpdfja:
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$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
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@echo "Running LaTeX files through platex and dvipdfmx..."
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$(MAKE) -C $(BUILDDIR)/latex all-pdf-ja
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@echo "pdflatex finished; the PDF files are in $(BUILDDIR)/latex."
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text:
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$(SPHINXBUILD) -b text $(ALLSPHINXOPTS) $(BUILDDIR)/text
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@echo
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@echo "Build finished. The text files are in $(BUILDDIR)/text."
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man:
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$(SPHINXBUILD) -b man $(ALLSPHINXOPTS) $(BUILDDIR)/man
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@echo
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@echo "Build finished. The manual pages are in $(BUILDDIR)/man."
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texinfo:
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$(SPHINXBUILD) -b texinfo $(ALLSPHINXOPTS) $(BUILDDIR)/texinfo
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@echo
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@echo "Build finished. The Texinfo files are in $(BUILDDIR)/texinfo."
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@echo "Run \`make' in that directory to run these through makeinfo" \
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"(use \`make info' here to do that automatically)."
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info:
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$(SPHINXBUILD) -b texinfo $(ALLSPHINXOPTS) $(BUILDDIR)/texinfo
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@echo "Running Texinfo files through makeinfo..."
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make -C $(BUILDDIR)/texinfo info
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@echo "makeinfo finished; the Info files are in $(BUILDDIR)/texinfo."
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gettext:
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$(SPHINXBUILD) -b gettext $(I18NSPHINXOPTS) $(BUILDDIR)/locale
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@echo
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@echo "Build finished. The message catalogs are in $(BUILDDIR)/locale."
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changes:
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$(SPHINXBUILD) -b changes $(ALLSPHINXOPTS) $(BUILDDIR)/changes
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@echo
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@echo "The overview file is in $(BUILDDIR)/changes."
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linkcheck:
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$(SPHINXBUILD) -b linkcheck $(ALLSPHINXOPTS) $(BUILDDIR)/linkcheck
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@echo
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@echo "Link check complete; look for any errors in the above output " \
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"or in $(BUILDDIR)/linkcheck/output.txt."
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doctest:
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$(SPHINXBUILD) -b doctest $(ALLSPHINXOPTS) $(BUILDDIR)/doctest
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@echo "Testing of doctests in the sources finished, look at the " \
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"results in $(BUILDDIR)/doctest/output.txt."
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xml:
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$(SPHINXBUILD) -b xml $(ALLSPHINXOPTS) $(BUILDDIR)/xml
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@echo
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@echo "Build finished. The XML files are in $(BUILDDIR)/xml."
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pseudoxml:
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$(SPHINXBUILD) -b pseudoxml $(ALLSPHINXOPTS) $(BUILDDIR)/pseudoxml
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@echo
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@echo "Build finished. The pseudo-XML files are in $(BUILDDIR)/pseudoxml."
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docs/ru/conf.py
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260
docs/ru/conf.py
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# -*- coding: utf-8 -*-
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#
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# ClickHouse documentation build configuration file, created by
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# sphinx-quickstart on Tue Mar 21 13:05:32 2017.
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#
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# This file is execfile()d with the current directory set to its
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# containing dir.
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#
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# Note that not all possible configuration values are present in this
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# autogenerated file.
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#
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# All configuration values have a default; values that are commented out
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# serve to show the default.
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import sys
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import os
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# If extensions (or modules to document with autodoc) are in another directory,
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# add these directories to sys.path here. If the directory is relative to the
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# documentation root, use os.path.abspath to make it absolute, like shown here.
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#sys.path.insert(0, os.path.abspath('.'))
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# -- General configuration ------------------------------------------------
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# If your documentation needs a minimal Sphinx version, state it here.
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#needs_sphinx = '1.0'
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# Add any Sphinx extension module names here, as strings. They can be
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# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
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# ones.
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extensions = [
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'sphinx.ext.mathjax',
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]
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# Add any paths that contain templates here, relative to this directory.
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templates_path = ['_templates']
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# The suffix of source filenames.
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source_suffix = '.rst'
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# The encoding of source files.
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#source_encoding = 'utf-8-sig'
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# The master toctree document.
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master_doc = 'index'
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# General information about the project.
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project = u'ClickHouse'
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copyright = u'2017, Alexey Milovidov'
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# The version info for the project you're documenting, acts as replacement for
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# |version| and |release|, also used in various other places throughout the
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# built documents.
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#
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# The short X.Y version.
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version = '1'
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# The full version, including alpha/beta/rc tags.
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release = '1'
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# The language for content autogenerated by Sphinx. Refer to documentation
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# for a list of supported languages.
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#language = None
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# There are two options for replacing |today|: either, you set today to some
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# non-false value, then it is used:
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#today = ''
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# Else, today_fmt is used as the format for a strftime call.
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#today_fmt = '%B %d, %Y'
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# List of patterns, relative to source directory, that match files and
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# directories to ignore when looking for source files.
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exclude_patterns = []
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# The reST default role (used for this markup: `text`) to use for all
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# documents.
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#default_role = None
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# If true, '()' will be appended to :func: etc. cross-reference text.
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#add_function_parentheses = True
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# If true, the current module name will be prepended to all description
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# unit titles (such as .. function::).
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#add_module_names = True
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# If true, sectionauthor and moduleauthor directives will be shown in the
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# output. They are ignored by default.
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#show_authors = False
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# The name of the Pygments (syntax highlighting) style to use.
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pygments_style = 'sphinx'
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# A list of ignored prefixes for module index sorting.
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#modindex_common_prefix = []
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# If true, keep warnings as "system message" paragraphs in the built documents.
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#keep_warnings = False
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# -- Options for HTML output ----------------------------------------------
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# The theme to use for HTML and HTML Help pages. See the documentation for
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# a list of builtin themes.
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html_theme = 'default'
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# Theme options are theme-specific and customize the look and feel of a theme
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# further. For a list of options available for each theme, see the
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# documentation.
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#html_theme_options = {}
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# Add any paths that contain custom themes here, relative to this directory.
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#html_theme_path = []
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# The name for this set of Sphinx documents. If None, it defaults to
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# "<project> v<release> documentation".
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#html_title = None
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# A shorter title for the navigation bar. Default is the same as html_title.
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#html_short_title = None
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# The name of an image file (relative to this directory) to place at the top
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# of the sidebar.
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#html_logo = None
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# The name of an image file (within the static path) to use as favicon of the
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# docs. This file should be a Windows icon file (.ico) being 16x16 or 32x32
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# pixels large.
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#html_favicon = None
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# Add any paths that contain custom static files (such as style sheets) here,
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# relative to this directory. They are copied after the builtin static files,
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# so a file named "default.css" will overwrite the builtin "default.css".
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html_static_path = ['_static']
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# Add any extra paths that contain custom files (such as robots.txt or
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# .htaccess) here, relative to this directory. These files are copied
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# directly to the root of the documentation.
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#html_extra_path = []
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# If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
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# using the given strftime format.
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#html_last_updated_fmt = '%b %d, %Y'
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# If true, SmartyPants will be used to convert quotes and dashes to
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# typographically correct entities.
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#html_use_smartypants = True
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# Custom sidebar templates, maps document names to template names.
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#html_sidebars = {}
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# Additional templates that should be rendered to pages, maps page names to
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# template names.
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#html_additional_pages = {}
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# If false, no module index is generated.
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#html_domain_indices = True
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# If false, no index is generated.
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#html_use_index = True
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# If true, the index is split into individual pages for each letter.
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#html_split_index = False
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# If true, links to the reST sources are added to the pages.
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#html_show_sourcelink = True
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# If true, "Created using Sphinx" is shown in the HTML footer. Default is True.
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#html_show_sphinx = True
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# If true, "(C) Copyright ..." is shown in the HTML footer. Default is True.
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#html_show_copyright = True
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# If true, an OpenSearch description file will be output, and all pages will
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# contain a <link> tag referring to it. The value of this option must be the
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# base URL from which the finished HTML is served.
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#html_use_opensearch = ''
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# This is the file name suffix for HTML files (e.g. ".xhtml").
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#html_file_suffix = None
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# Output file base name for HTML help builder.
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htmlhelp_basename = 'ClickHousedoc'
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# -- Options for LaTeX output ---------------------------------------------
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latex_elements = {
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# The paper size ('letterpaper' or 'a4paper').
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#'papersize': 'letterpaper',
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# The font size ('10pt', '11pt' or '12pt').
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#'pointsize': '10pt',
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# Additional stuff for the LaTeX preamble.
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#'preamble': '',
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}
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# Grouping the document tree into LaTeX files. List of tuples
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# (source start file, target name, title,
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# author, documentclass [howto, manual, or own class]).
|
||||
latex_documents = [
|
||||
('index', 'ClickHouse.tex', u'ClickHouse Documentation',
|
||||
u'Alexey Milovidov', 'manual'),
|
||||
]
|
||||
|
||||
# The name of an image file (relative to this directory) to place at the top of
|
||||
# the title page.
|
||||
#latex_logo = None
|
||||
|
||||
# For "manual" documents, if this is true, then toplevel headings are parts,
|
||||
# not chapters.
|
||||
#latex_use_parts = False
|
||||
|
||||
# If true, show page references after internal links.
|
||||
#latex_show_pagerefs = False
|
||||
|
||||
# If true, show URL addresses after external links.
|
||||
#latex_show_urls = False
|
||||
|
||||
# Documents to append as an appendix to all manuals.
|
||||
#latex_appendices = []
|
||||
|
||||
# If false, no module index is generated.
|
||||
#latex_domain_indices = True
|
||||
|
||||
|
||||
# -- Options for manual page output ---------------------------------------
|
||||
|
||||
# One entry per manual page. List of tuples
|
||||
# (source start file, name, description, authors, manual section).
|
||||
man_pages = [
|
||||
('index', 'clickhouse', u'ClickHouse Documentation',
|
||||
[u'Alexey Milovidov'], 1)
|
||||
]
|
||||
|
||||
# If true, show URL addresses after external links.
|
||||
#man_show_urls = False
|
||||
|
||||
|
||||
# -- Options for Texinfo output -------------------------------------------
|
||||
|
||||
# Grouping the document tree into Texinfo files. List of tuples
|
||||
# (source start file, target name, title, author,
|
||||
# dir menu entry, description, category)
|
||||
texinfo_documents = [
|
||||
('index', 'ClickHouse', u'ClickHouse Documentation',
|
||||
u'Alexey Milovidov', 'ClickHouse', 'One line description of project.',
|
||||
'Miscellaneous'),
|
||||
]
|
||||
|
||||
# Documents to append as an appendix to all manuals.
|
||||
#texinfo_appendices = []
|
||||
|
||||
# If false, no module index is generated.
|
||||
#texinfo_domain_indices = True
|
||||
|
||||
# How to display URL addresses: 'footnote', 'no', or 'inline'.
|
||||
#texinfo_show_urls = 'footnote'
|
||||
|
||||
# If true, do not generate a @detailmenu in the "Top" node's menu.
|
||||
#texinfo_no_detailmenu = False
|
@ -1341,7 +1341,7 @@ n и m должны быть неотрицательными целыми чи
|
||||
В таких случаях всегда следует использовать GLOBAL IN вместо IN. Рассмотрим его работу для запроса
|
||||
|
||||
.. code-block:: sql
|
||||
|
||||
|
||||
SELECT uniq(UserID) FROM distributed_table WHERE CounterID = 101500 AND UserID GLOBAL IN (SELECT UserID FROM distributed_table WHERE CounterID = 34)
|
||||
|
||||
На сервере-инициаторе запроса будет выполнен подзапрос
|
||||
@ -1353,7 +1353,7 @@ n и m должны быть неотрицательными целыми чи
|
||||
, и результат будет сложен во временную таблицу в оперативке. Затем запрос будет отправлен на каждый удалённый сервер в виде
|
||||
|
||||
.. code-block:: sql
|
||||
|
||||
|
||||
SELECT uniq(UserID) FROM local_table WHERE CounterID = 101500 AND UserID GLOBAL IN _data1
|
||||
|
||||
, и вместе с запросом, на каждый удалённый сервер будет отправлена временная таблица _data1 (имя временной таблицы - implementation defined).
|
||||
@ -1385,14 +1385,14 @@ n и m должны быть неотрицательными целыми чи
|
||||
В секциях ``GROUP BY``, ``ORDER BY``, в отличие от диалекта MySQL, и в соответствии со стандартным SQL, не поддерживаются позиционные аргументы.
|
||||
Например, если вы напишите ``GROUP BY 1, 2`` - то это будет воспринято, как группировка по константам (то есть, агрегация всех строк в одну).
|
||||
|
||||
Вы можете использовать синонимы (алиасы AS) в любом месте запроса.
|
||||
Вы можете использовать синонимы (алиасы ``AS``) в любом месте запроса.
|
||||
|
||||
В любом месте запроса, вместо выражения, может стоять звёздочка. При анализе запроса звёздочка раскрывается в список всех столбцов таблицы (за исключением MATERIALIZED и ALIAS столбцов). Есть лишь немного случаев, когда оправдано использовать звёздочку:
|
||||
В любом месте запроса, вместо выражения, может стоять звёздочка. При анализе запроса звёздочка раскрывается в список всех столбцов таблицы (за исключением ``MATERIALIZED`` и ``ALIAS`` столбцов). Есть лишь немного случаев, когда оправдано использовать звёздочку:
|
||||
|
||||
* при создании дампа таблицы;
|
||||
* для таблиц, содержащих всего несколько столбцов - например, системных таблиц;
|
||||
* для получения информации о том, какие столбцы есть в таблице; в этом случае, укажите LIMIT 1. Но лучше используйте запрос DESC TABLE;
|
||||
* при наличии сильной фильтрации по небольшому количеству столбцов с помощью PREWHERE;
|
||||
* для получения информации о том, какие столбцы есть в таблице; в этом случае, укажите ``LIMIT 1``. Но лучше используйте запрос ``DESC TABLE``;
|
||||
* при наличии сильной фильтрации по небольшому количеству столбцов с помощью ``PREWHERE``;
|
||||
* в подзапросах (так как из подзапросов выкидываются столбцы, не нужные для внешнего запроса).
|
||||
|
||||
В других случаях использование звёздочки является издевательством над системой, так как вместо преимуществ столбцовой СУБД вы получаете недостатки. То есть использовать звёздочку не рекомендуется.
|
||||
@ -1402,16 +1402,32 @@ KILL QUERY
|
||||
|
||||
.. code-block:: sql
|
||||
|
||||
KILL QUERY WHERE expression_for_system.processes [SYNC|ASYNC|TEST] [FORMAT format]
|
||||
KILL QUERY WHERE <where expression to SELECT FROM system.processes query> [SYNC|ASYNC|TEST] [FORMAT format]
|
||||
|
||||
Пытается завершить исполняющиеся в данный момент запросы.
|
||||
Запросы для завершения выбираются из таблицы system.processes для которых выражение expression_for_system.processes истинно.
|
||||
|
||||
Примеры:
|
||||
|
||||
.. code-block:: sql
|
||||
|
||||
KILL QUERY WHERE query_id='2-857d-4a57-9ee0-327da5d60a90'
|
||||
|
||||
Завершает все запросы с указанным query_id.
|
||||
|
||||
.. code-block:: sql
|
||||
|
||||
KILL QUERY WHERE user='username' SYNC
|
||||
|
||||
Синхронно завершает все запросы пользователя ``username``.
|
||||
|
||||
Readonly-пользователи могут совершать только свои запросы.
|
||||
По-умолчанию используется асинхронный вариант запроса (ASYNC), который завершается не ожидая завершения запросов.
|
||||
Синхронный вариант (SYNC) ожидает завершения всех запросов и построчно выводит информацию о процессах по ходу их завершения.
|
||||
По-умолчанию используется асинхронный вариант запроса (``ASYNC``), который завершается не ожидая завершения запросов.
|
||||
Синхронный вариант (``SYNC``) ожидает завершения всех запросов и построчно выводит информацию о процессах по ходу их завершения.
|
||||
Ответ содержит колонку ``kill_status``, которая может принимать следующие значения:
|
||||
|
||||
#. 'finished' - запрос успешно завершился;
|
||||
#. 'waiting' - запросу отправлен сигнал завершения, ожидается его завершение;
|
||||
#. остальные значения описывают причину невозможности завершения запроса.
|
||||
|
||||
Тестовый вариант запроса (TEST) только проверяет права пользователя и выводит список запросов для завершения.
|
||||
Тестовый вариант запроса (``TEST``) только проверяет права пользователя и выводит список запросов для завершения.
|
||||
|
Loading…
Reference in New Issue
Block a user