[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=93447=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-93447
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 20/Apr/18 21:18
Start Date: 20/Apr/18 21:18
Worklog Time Spent: 10m 
  Work Description: jkff commented on issue #5109: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/5109#issuecomment-383225368
 
 
   Thank you!


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Issue Time Tracking
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Worklog Id: (was: 93447)
Time Spent: 4h  (was: 3h 50m)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 4h
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=93446=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-93446
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 20/Apr/18 21:18
Start Date: 20/Apr/18 21:18
Worklog Time Spent: 10m 
  Work Description: jkff closed pull request #5109: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/5109
 
 
   

This is a PR merged from a forked repository.
As GitHub hides the original diff on merge, it is displayed below for
the sake of provenance:

As this is a foreign pull request (from a fork), the diff is supplied
below (as it won't show otherwise due to GitHub magic):

diff --git 
a/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java 
b/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java
index 31481e28577..cd13a24d142 100644
--- a/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java
+++ b/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java
@@ -159,7 +159,9 @@
* @param  Type of the data to be read.
*/
   public static  Read read() {
-return new AutoValue_JdbcIO_Read.Builder().build();
+return new AutoValue_JdbcIO_Read.Builder()
+.setFetchSize(DEFAULT_FETCH_SIZE)
+.build();
   }
 
   /**
@@ -170,10 +172,13 @@
* @param  Type of the data to be read.
*/
   public static  ReadAll readAll() {
-return new AutoValue_JdbcIO_ReadAll.Builder().build();
+return new AutoValue_JdbcIO_ReadAll.Builder()
+.setFetchSize(DEFAULT_FETCH_SIZE)
+.build();
   }
 
   private static final long DEFAULT_BATCH_SIZE = 1000L;
+  private static final int DEFAULT_FETCH_SIZE = 50_000;
 
   /**
* Write data to a JDBC datasource.
@@ -372,6 +377,7 @@ DataSource buildDatasource() throws Exception {
 @Nullable abstract StatementPreparator getStatementPreparator();
 @Nullable abstract RowMapper getRowMapper();
 @Nullable abstract Coder getCoder();
+abstract int getFetchSize();
 
 abstract Builder toBuilder();
 
@@ -382,6 +388,7 @@ DataSource buildDatasource() throws Exception {
   abstract Builder setStatementPreparator(StatementPreparator 
statementPreparator);
   abstract Builder setRowMapper(RowMapper rowMapper);
   abstract Builder setCoder(Coder coder);
+  abstract Builder setFetchSize(int fetchSize);
   abstract Read build();
 }
 
@@ -414,6 +421,16 @@ DataSource buildDatasource() throws Exception {
   return toBuilder().setCoder(coder).build();
 }
 
+/**
+ * This method is used to set the size of the data that is going to be 
fetched and loaded in
+ * memory per every database call. Please refer to: {@link 
java.sql.Statement#setFetchSize(int)}
+ * It should ONLY be used if the default value throws memory errors.
+ */
+public Read withFetchSize(int fetchSize) {
+  checkArgument(fetchSize > 0, "fetch size must be > 0");
+  return toBuilder().setFetchSize(fetchSize).build();
+}
+
 @Override
 public PCollection expand(PBegin input) {
   checkArgument(getQuery() != null, "withQuery() is required");
@@ -430,6 +447,7 @@ DataSource buildDatasource() throws Exception {
   .withQuery(getQuery())
   .withCoder(getCoder())
   .withRowMapper(getRowMapper())
+  .withFetchSize(getFetchSize())
   .withParameterSetter(
   (element, preparedStatement) -> {
 if (getStatementPreparator() != null) {
@@ -459,6 +477,7 @@ public void populateDisplayData(DisplayData.Builder 
builder) {
 @Nullable abstract PreparedStatementSetter 
getParameterSetter();
 @Nullable abstract RowMapper getRowMapper();
 @Nullable abstract Coder getCoder();
+abstract int getFetchSize();
 
 abstract Builder toBuilder();
 
@@ -471,6 +490,7 @@ public void populateDisplayData(DisplayData.Builder 
builder) {
   PreparedStatementSetter parameterSetter);
   abstract Builder setRowMapper(RowMapper 
rowMapper);
   abstract Builder setCoder(Coder coder);
+  abstract Builder setFetchSize(int fetchSize);
   abstract ReadAll build();
 }
 
@@ -508,6 +528,16 @@ public void populateDisplayData(DisplayData.Builder 
builder) {
   return toBuilder().setCoder(coder).build();
 }
 
+/**
+ * This method is used to set the size of the data that is going to be 
fetched and loaded in
+ * memory per every database call. Please refer to: {@link 
java.sql.Statement#setFetchSize(int)}
+ * It should ONLY be used if the 

[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=93199=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-93199
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 20/Apr/18 13:07
Start Date: 20/Apr/18 13:07
Worklog Time Spent: 10m 
  Work Description: evindj commented on issue #5109: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/5109#issuecomment-383090055
 
 
   @jkff will check that later today. 


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Issue Time Tracking
---

Worklog Id: (was: 93199)
Time Spent: 3h 40m  (was: 3.5h)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 3h 40m
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=92880=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-92880
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 19/Apr/18 22:21
Start Date: 19/Apr/18 22:21
Worklog Time Spent: 10m 
  Work Description: jkff commented on issue #5109: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/5109#issuecomment-382898723
 
 
   The Go precommit is a flake, but in Java there seems to be a couple of final 
simple checkstyle errors (line too long) remaining.


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Issue Time Tracking
---

Worklog Id: (was: 92880)
Time Spent: 3h 20m  (was: 3h 10m)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 3h 20m
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=92884=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-92884
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 19/Apr/18 22:21
Start Date: 19/Apr/18 22:21
Worklog Time Spent: 10m 
  Work Description: jkff commented on issue #5109: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/5109#issuecomment-382898800
 
 
   You can reproduce by running ./gradlew :beam-sdks-java-io-jdbc:checkstyleMain


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Issue Time Tracking
---

Worklog Id: (was: 92884)
Time Spent: 3.5h  (was: 3h 20m)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 3.5h
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=92793=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-92793
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 19/Apr/18 18:57
Start Date: 19/Apr/18 18:57
Worklog Time Spent: 10m 
  Work Description: jkff commented on issue #5109: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/5109#issuecomment-382844652
 
 
   retest this please


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Issue Time Tracking
---

Worklog Id: (was: 92793)
Time Spent: 3h 10m  (was: 3h)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 3h 10m
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=91037=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-91037
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 14/Apr/18 00:59
Start Date: 14/Apr/18 00:59
Worklog Time Spent: 10m 
  Work Description: jkff commented on a change in pull request #5109: 
[BEAM-3714]modified result set to be forward only and read only
URL: https://github.com/apache/beam/pull/5109#discussion_r181536055
 
 

 ##
 File path: 
sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java
 ##
 @@ -414,6 +421,15 @@ DataSource buildDatasource() throws Exception {
   return toBuilder().setCoder(coder).build();
 }
 
+/**
+ * This method used to set the size of the data that is going to be 
fetched from the database.
 
 Review comment:
   This description is a bit confusing - it's not the size of the whole data, 
it's how much will be fetched per every database call and kept in memory. Maybe 
just link to Statement.setFetchSize.


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Issue Time Tracking
---

Worklog Id: (was: 91037)
Time Spent: 2h 50m  (was: 2h 40m)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 2h 50m
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=91038=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-91038
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 14/Apr/18 00:59
Start Date: 14/Apr/18 00:59
Worklog Time Spent: 10m 
  Work Description: jkff commented on a change in pull request #5109: 
[BEAM-3714]modified result set to be forward only and read only
URL: https://github.com/apache/beam/pull/5109#discussion_r181536064
 
 

 ##
 File path: 
sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java
 ##
 @@ -508,6 +527,15 @@ public void populateDisplayData(DisplayData.Builder 
builder) {
   return toBuilder().setCoder(coder).build();
 }
 
+/**
+ * This method used to set the size of the data that is going to be 
fetched from the database.
 
 Review comment:
   Likewise


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Issue Time Tracking
---

Worklog Id: (was: 91038)
Time Spent: 3h  (was: 2h 50m)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 3h
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=90263=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-90263
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 12/Apr/18 01:49
Start Date: 12/Apr/18 01:49
Worklog Time Spent: 10m 
  Work Description: evindj commented on issue #5109: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/5109#issuecomment-380648883
 
 
   @jkff I add to close the other PR rebasing  added some other commits to the 
it that could have been confusing.


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Issue Time Tracking
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Worklog Id: (was: 90263)
Time Spent: 2h 40m  (was: 2.5h)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 2h 40m
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

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 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=90262=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-90262
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 12/Apr/18 01:47
Start Date: 12/Apr/18 01:47
Worklog Time Spent: 10m 
  Work Description: evindj opened a new pull request #5109: 
[BEAM-3714]modified result set to be forward only and read only
URL: https://github.com/apache/beam/pull/5109
 
 
   DESCRIPTION HERE
   
   
   
   Follow this checklist to help us incorporate your contribution quickly and 
easily:
   
- [ ] Make sure there is a [JIRA 
issue](https://issues.apache.org/jira/projects/BEAM/issues/) filed for the 
change (usually before you start working on it).  Trivial changes like typos do 
not require a JIRA issue.  Your pull request should address just this issue, 
without pulling in other changes.
- [ ] Format the pull request title like `[BEAM-XXX] Fixes bug in 
ApproximateQuantiles`, where you replace `BEAM-XXX` with the appropriate JIRA 
issue.
- [ ] Write a pull request description that is detailed enough to 
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  - [ ] What the pull request does
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Issue Time Tracking
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Worklog Id: (was: 90262)
Time Spent: 2.5h  (was: 2h 20m)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 2.5h
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=90203=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-90203
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 11/Apr/18 22:38
Start Date: 11/Apr/18 22:38
Worklog Time Spent: 10m 
  Work Description: jkff commented on issue #4786: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/4786#issuecomment-380617977
 
 
   (sorry, was on leave) - Okay, let's keep the parameter then. I'll be happy 
to merge after the following:
   
   - Please rebase
   - Please document the `withFetchSize` method and say that it should be used 
ONLY if the default value produces out-of-memory errors.


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Issue Time Tracking
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Worklog Id: (was: 90203)
Time Spent: 2h 10m  (was: 2h)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 2h 10m
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=86338=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-86338
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 01/Apr/18 02:12
Start Date: 01/Apr/18 02:12
Worklog Time Spent: 10m 
  Work Description: evindj commented on issue #4786: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/4786#issuecomment-377737658
 
 
   @jkff  I can still revert the set batch size if you have a strong feeling on 
this.


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Issue Time Tracking
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Worklog Id: (was: 86338)
Time Spent: 2h  (was: 1h 50m)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 2h
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=81611=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-81611
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 17/Mar/18 20:59
Start Date: 17/Mar/18 20:59
Worklog Time Spent: 10m 
  Work Description: jkff commented on issue #4786: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/4786#issuecomment-373952197
 
 
   Thanks for testing! What use case do you have in mind where the default 
fetch size will behave very poorly so the user needs to configure it 
differently?


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Issue Time Tracking
---

Worklog Id: (was: 81611)
Time Spent: 1h 40m  (was: 1.5h)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 1h 40m
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=81608=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-81608
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 17/Mar/18 20:38
Start Date: 17/Mar/18 20:38
Worklog Time Spent: 10m 
  Work Description: evindj commented on issue #4786: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/4786#issuecomment-372397754
 
 
   Hi Eugene, I could not find time for it last week but updates comming up
   shortly
   
   On Mon, Mar 12, 2018 at 12:41 PM Eugene Kirpichov 
   wrote:
   
   > @evindj  Any updates here?
   >
   > —
   > You are receiving this because you were mentioned.
   >
   >
   > Reply to this email directly, view it on GitHub
   > , or mute
   > the thread
   > 

   > .
   >
   -- 
   
   *DJIOFACK INNOCENT*
   *"Be better than the day before!" -*
   
   


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Issue Time Tracking
---

Worklog Id: (was: 81608)
Time Spent: 1.5h  (was: 1h 20m)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 1.5h
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=81607=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-81607
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 17/Mar/18 20:29
Start Date: 17/Mar/18 20:29
Worklog Time Spent: 10m 
  Work Description: evindj commented on issue #4786: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/4786#issuecomment-373950328
 
 
   @jkff I tested this with a DB I setup on cloud SQL without  running into 
memory issues. I understand that the design goal around BEAM is to offload the 
user of performance tuning. I do think for this use case, It is still worth 
giving a way users could set the batch size.


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Issue Time Tracking
---

Worklog Id: (was: 81607)
Time Spent: 1h 20m  (was: 1h 10m)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 1h 20m
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=79535=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-79535
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 12/Mar/18 17:38
Start Date: 12/Mar/18 17:38
Worklog Time Spent: 10m 
  Work Description: evindj commented on issue #4786: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/4786#issuecomment-372397754
 
 
   Hi Eugene, I could not find time for it last week but updates comming up
   shortly
   
   On Mon, Mar 12, 2018 at 12:41 PM Eugene Kirpichov 
   wrote:
   
   > @evindj  Any updates here?
   >
   > —
   > You are receiving this because you were mentioned.
   >
   >
   > Reply to this email directly, view it on GitHub
   > , or mute
   > the thread
   > 

   > .
   >
   -- 
   
   *DJIOFACK INNOCENT*
   *"Be better than the day before!" -*
   *+1 404 751 8024*
   


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Issue Time Tracking
---

Worklog Id: (was: 79535)
Time Spent: 1h 10m  (was: 1h)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 1h 10m
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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[jira] [Work logged] (BEAM-3714) JdbcIO.read() should create a forward-only, read-only result set

[ASF GitHub Bot (JIRA)]

 [ 
https://issues.apache.org/jira/browse/BEAM-3714?focusedWorklogId=79517=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-79517
 ]

ASF GitHub Bot logged work on BEAM-3714:


Author: ASF GitHub Bot
Created on: 12/Mar/18 16:41
Start Date: 12/Mar/18 16:41
Worklog Time Spent: 10m 
  Work Description: jkff commented on issue #4786: [BEAM-3714]modified 
result set to be forward only and read only
URL: https://github.com/apache/beam/pull/4786#issuecomment-372377397
 
 
   @evindj Any updates here?


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Issue Time Tracking
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Worklog Id: (was: 79517)
Time Spent: 1h  (was: 50m)

> JdbcIO.read() should create a forward-only, read-only result set
> 
>
> Key: BEAM-3714
> URL: https://issues.apache.org/jira/browse/BEAM-3714
> Project: Beam
>  Issue Type: Bug
>  Components: io-java-jdbc
>Reporter: Eugene Kirpichov
>Assignee: Innocent
>Priority: Major
>  Time Spent: 1h
>  Remaining Estimate: 0h
>
> [https://stackoverflow.com/questions/48784889/streaming-data-from-cloudsql-into-dataflow/48819934#48819934]
>  - a user is trying to load a large table from MySQL, and the MySQL JDBC 
> driver requires special measures when loading large result sets.
> JdbcIO currently calls simply "connection.prepareStatement(query)" 
> https://github.com/apache/beam/blob/bb8c12c4956cbe3c6f2e57113e7c0ce2a5c05009/sdks/java/io/jdbc/src/main/java/org/apache/beam/sdk/io/jdbc/JdbcIO.java#L508
>  - it should specify type TYPE_FORWARD_ONLY and concurrency CONCUR_READ_ONLY 
> - these values should always be used.
> Seems that different databases have different requirements for streaming 
> result sets.
> E.g. MySQL requires setting fetch size; PostgreSQL says "The Connection must 
> not be in autocommit mode." 
> https://jdbc.postgresql.org/documentation/head/query.html#query-with-cursor . 
> Oracle, I think, doesn't have any special requirements but I don't know. 
> Fetch size should probably still be set to a reasonably large value.
> Seems that the common denominator of these requirements is: set fetch size to 
> a reasonably large but not maximum value; disable autocommit (there's nothing 
> to commit in read() anyway).



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