notnull

Drop rows of pandas dataframe that don't have finite values in certain variable(s)

由 心已入冬 提交于 2019-12-08 09:54:58
问题 I cannot see what the built-in function is for the following simple but seemingly common/useful task: Drop rows which have no value for any of my key columns. def keepIfPopulated(adf,interestingVars): good=0 for vv in interestingVars: good+=adf[vv].notnull() return(adf[good>0]) If there was just one column of interest, I could choose to keep it, but most pandas functions take one or more labels as arguments, so this question is about how to check on one or more columns at once. 回答1: adf = adf

Oracle - Error: 'ORA-01400: cannot insert NULL into

由 断了今生、忘了曾经 提交于 2019-12-07 21:20:02
问题 I'm trying to insert a record into a table, but getting the error - 'ORA-01400: cannot insert NULL into (....'. The table structure is: I migrate from Mysql to Oracle. On Mysql this works, but on Oracle it is not working. How can I fix this? Do I need write all column insert query or unselect not null option 回答1: Try this: create or replace trigger EDITIONS_COR before insert or update on EDITIONS for each row begin if INSERTING then select EDITIONS_SEQ.nextval into :new.ID from DUAL; end if;

prevent autoincrementing integer primary key?

由 蹲街弑〆低调 提交于 2019-12-07 06:43:16
问题 I have a sqlite table (sqlite version 3.7.3) where nulls inserted into the primary key column are being undesirably auto-incremented: sqlite> CREATE TABLE foo(bar INTEGER NOT NULL PRIMARY KEY); sqlite> INSERT INTO foo(bar) VALUES(NULL); sqlite> SELECT * FROM foo; 1 In the sqlite docs, it shows that adding the AUTOINCREMENT keyword to the column should create this behavior, but there doesn't appear to be a keyword to prevent the auto incrementing... I also found that I can build sqlite with

Oracle - Error: 'ORA-01400: cannot insert NULL into

由 人盡茶涼 提交于 2019-12-06 06:19:53
I'm trying to insert a record into a table, but getting the error - 'ORA-01400: cannot insert NULL into (....'. The table structure is: I migrate from Mysql to Oracle. On Mysql this works, but on Oracle it is not working. How can I fix this? Do I need write all column insert query or unselect not null option user3546225 Try this: create or replace trigger EDITIONS_COR before insert or update on EDITIONS for each row begin if INSERTING then select EDITIONS_SEQ.nextval into :new.ID from DUAL; end if; :new.CORDATE:=SYSDATE; :new.USERNAME:=USER; end; 来源： https://stackoverflow.com/questions

java/beans validation - collection/map does not contain nulls

由 扶醉桌前 提交于 2019-12-06 05:51:07
There is the @NotNull annotation which validates that a certain object is not null. There is the @NotEmpty annotation which validates that a certain collection/map/string/... is not empty. Is there also an annotation which valides that a certain collection/map does not contain any nulls? I am unable to find it. It seems so basic, that I believe it must be in the JSR-303 spec. There is no such built-in constraints. You can easily write your custom constraints, eg @NoNullElements, which does what you want. Refer to the Refer to the documentation http://docs.jboss.org/hibernate/stable/validator

@Nullable and SonarQube 'Conditionally executed blocks should be reachable' warning

由 ♀尐吖头ヾ 提交于 2019-12-05 03:51:33
Package has following package-info.java: @ParametersAreNonnullByDefault package foo; import javax.annotation.ParametersAreNonnullByDefault; Class has the following method: private static String toIsoString(@Nullable Instant dateTime) { return dateTime == null ? null : dateTime.toString(); } On which SonarQube (Version 6.2, SonarJava 4.14.0.11784) gives the following warning (squid:S2583): How can I convince SonarQube that the code is actually correct? Interestingly, SonarLint plugin (3.0.0.2041) in Idea doesn't generate the same warning. Apparently, this problem was caused by us using sonar

SQL Not Empty instead of Not NULL

由 拟墨画扇 提交于 2019-12-04 10:28:32
问题 I am using postgreSQL. I have a column that: NOT NULL However when I want to insert a row with an empty string as like: '' it doesn't give me an error and accepts. How can I check insert value should be not empty ? (Neither empty nor null) PS: My column defined as: "ads" character varying(60) NOT NULL 回答1: Add a constraint to column definition. For example something like: ads character varying(60) NOT NULL CHECK (ads <> '') For more, see http://www.postgresql.org/docs/current/static/ddl

Insert default value when null is inserted

由 China☆狼群 提交于 2019-12-03 12:38:08
I have an Oracle database, and a table with several not null columns, all with default values. I would like to use one insert statement for any data I want to insert, and don't bother to check if the values inserted are nulls or not. Is there any way to fall back to default column value when null is inserted? I have this code: <?php if (!empty($values['not_null_column_with_default_value'])) { $insert = " INSERT INTO schema.my_table ( pk_column, other_column, not_null_column_with_default_value) VALUES (:pk_column,:other_column,:not_null_column_with_default_value) "; } else { $insert = " INSERT

SQL Not Empty instead of Not NULL

由 回眸只為那壹抹淺笑 提交于 2019-12-03 06:38:58
I am using postgreSQL. I have a column that: NOT NULL However when I want to insert a row with an empty string as like: '' it doesn't give me an error and accepts. How can I check insert value should be not empty ? (Neither empty nor null) PS: My column defined as: "ads" character varying(60) NOT NULL Add a constraint to column definition. For example something like: ads character varying(60) NOT NULL CHECK (ads <> '') For more, see http://www.postgresql.org/docs/current/static/ddl-constraints.html micfra Found in the current documentation of postgreSQL you can do the following to achieve what

Ruby on Rails: How do I add a not null constraint to an existing column using a migration?

由 …衆ロ難τιáo~ 提交于 2019-12-03 03:21:53
问题 In my Rails (3.2) app, I have a bunch of tables in my database but I forgot to add a few not null constraints. I've googled around but I can't find how to write a migration which adds not null to an existing column. TIA. 回答1: For Rails 4+, nates' answer (using change_column_null) is better. Pre-Rails 4, try change_column. 回答2: You can also use change_column_null: change_column_null :table_name, :column_name, false 回答3: 1) FIRST: Add column with default value 2) THEN: Remove default value add
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