m

db/nosql/column/clickhouse/clickhouse.txt

@@ -22,10 +22,7 @@ https://clickhouse.com/docs/en/integrations/java/jdbc-driver
 compression
 https://habr.com/en/company/yandex/blog/457612/
 
-lsm
-https://habr.com/ru/companies/wildberries/articles/821865/
-
-internals
+internals, lsm
 https://habr.com/ru/companies/wildberries/articles/821865/
     system.parts
 

db/nosql/column/clickhouse/docs/tips.txt

@@ -0,0 +1,2 @@
+2023
+https://habr.com/ru/articles/743772/

db/nosql/column/clickhouse/feature/agg.txt

@@ -0,0 +1,5 @@
+2024
+https://habr.com/ru/companies/oleg-bunin/articles/836078/
+    ! need to directly provide consistence of predaggr-table and src-one
+    !   ? using materialized-views (but m-v does not trigger updates/deletes)
+    ! projections - clickhouse makes automatically

db/nosql/column/clickhouse/feature/array.txt

@@ -0,0 +1,4 @@
+2020
+https://altinity.com/blog/harnessing-the-power-of-clickhouse-arrays-part-1
+https://altinity.com/blog/harnessing-the-power-of-clickhouse-arrays-part-2
+https://altinity.com/blog/harnessing-the-power-of-clickhouse-arrays-part-3

db/nosql/column/clickhouse/feature/dictionary.txt

@@ -0,0 +1,6 @@
+https://clickhouse.com/docs/en/sql-reference/dictionaries
+https://clickhouse.com/docs/en/sql-reference/functions/ext-dict-functions
+https://clickhouse.com/docs/en/sql-reference/functions/ym-dict-functions
+
+2024
+https://habr.com/ru/companies/oleg-bunin/articles/836078/

db/nosql/column/clickhouse/feature/engines.txt

@@ -1,4 +1,19 @@
 https://clickhouse.com/docs/ru/engines/table-engines
 https://clickhouse.com/docs/ru/engines/table-engines/mergetree-family
 https://clickhouse.com/docs/ru/engines/table-engines/mergetree-family/replacingmergetree
+    only eventually dedups (and on mutations)
 https://clickhouse.com/docs/en/engines/table-engines/special/join
+
+https://clickhouse.com/docs/en/guides/developer/deduplication
+https://kb.altinity.com/altinity-kb-schema-design/insert_deduplication/
+
+2024
+https://habr.com/ru/companies/oleg-bunin/articles/836078/
+    select ... final
+    optimize table <> final -- for replacingmergetree only
+    ! clickhouse has no transactionality !
+    index granularity (8192 - num of rows to read at once)
+    primary index is stored in RAM
+2021
+https://habr.com/ru/articles/539538/
+    ! need to read

db/nosql/column/clickhouse/feature/index.txt

@@ -0,0 +1,4 @@
+https://clickhouse-docs.vercel.app/docs/en/optimize/sparse-primary-indexes
+    ! each part has its own primary index
+    sparse index - one 'mark' per group of rows 'granule'
+    it must fit into the RAM

db/nosql/column/clickhouse/feature/internals.txt

@@ -13,6 +13,8 @@ https://clickhouse.com/docs/en/optimize/skipping-indexes
 
 2023
 https://clickhouse.com/blog/handling-updates-and-deletes-in-clickhouse
+https://habr.com/ru/companies/oleg-bunin/articles/726570/
+    ! perf-opt
 
 system db
 \c system

pl/java/libfws/spring/data/jdbc/docs/articles.txt

@@ -1,5 +1,7 @@
-2022
 https://www.baeldung.com/java-jdbc
+https://www.baeldung.com/spring-data-jdbc-intro
+
+2022
 https://thorben-janssen.com/spring-data-jdbc-sequence/
     https://habr.com/ru/company/otus/blog/687386/
 https://thorben-janssen.com/spring-data-jdbc-custom-queries-and-projections/

pl/java/libfws/spring/data/jdbc/features/query-methods.txt

@@ -0,0 +1 @@
+https://docs.spring.io/spring-data/relational/reference/jdbc/query-methods.html