is_null()-is_null()文档介绍内容-阿里云

alicloud_disk

must contain only alphanumeric characters or hyphens,such as"-",".","_",and must not begin or end with a hyphen,and must not begin with http:// or https://. Default value is null.description-(Optional)Description of the ...

运算符

SELECT*FROM user WHERE is_female is null;SELECT*FROM user WHERE is_female is not null;SELECT*FROM user WHERE user_id in(0001,0010);SELECT*FROM user WHERE user_name like 'M%';在执行部分关系运算之前，您首先需要进行类型转换，...

MySQL函数支持

NOT&,~,^,>>,,&,XOR GREATEST,LEAST IN,NOT IN LIKE,NOT LIKE SIMILAR TO,NOT SIMILAR TO,REGEXP,NOT REGEXP,RLIKE,NOT RLIKE IS,IS NOT,IS NOT NULL,IS NULL INTERVAL BETWEEN AND BIT_COUNT 条件函数 CASE WHEN[test1]THEN[result1]…...

如何优化数据全量抽取

gmt_create,id limit pageSize-lastMaxGmtCreate is null select*from t_order where user_id=xxx and((gmt_create is not null)or(gmt_create is null and id>lastMaxId))order by user_id,gmt_create,id limit pageSize

SELECT

IS NULL 空值判断 SELECT*FROM Test WHERE USERID IS NULL;IS NOT NULL 非空值判断 SELECT*FROM Test WHERE USERID IS NOT NULL;AND 对两个或两个以上的条件记录数据进行过滤，如果第一个条件和第二个条件都满足，则AND运算符显示一条记录...

alicloud_slb_server_certificate

certificate_id is null,it is required,otherwise it is ignored.private_key-(Optional,ForceNew)the content of privat key of the ssl certificate specified by server_certificate.where alicloud_certificate_id is null,it is ...

TRIM

FOR i IN sparse_arr.FIRST.sparse_arr.LAST LOOP IF sparse_arr(i)IS NULL THEN v_results:=v_results|'NULL ';ELSE v_results:=v_results|sparse_arr(i)|' ';END IF;END LOOP;DBMS_OUTPUT.PUT_LINE('Results:'|v_results);END;COUNT:5 ...

JSON

IS NULL或IS NOT NULL查询 SELECT id,vj FROM json_test WHERE json_extract(vj,'$.remark')is null;SELECT id,vj FROM json_test WHERE json_extract(vj,'$.name')is not null;IN 查询 SELECT id,vj FROM json_test WHERE json_extract(vj...

运算符

A IS NULL A为NULL，返回TRUE，否则返回FALSE。A IS NOT NULL A不为NULL，返回TRUE，否则返回FALSE。A LIKE B 如果A或B为NULL，返回NULL。A为字符串，B为要匹配的模式，如果匹配，返回TRUE，否则返回FALSE。百分号（%）匹配任意多个字符。...

JSON索引（2.0版）

IS NULL/IS NOT NULL查询 select id,json_test from json_tbl where json_extract(json_test,'$.remark')is null;select id,json_test from json_tbl where json_extract(json_test,'$.name')is null;select id,json_test from json_tbl ...

alicloud_ecs_disk

false.description-(Optional)Description of the disk.This description can have a string of 2 to 256 characters,It cannot begin with http:// or https://. Default value is null.disk_name-(Optional,Computed)Name of the ECS ...

错误码

错误码错误码值错误消息描述 SUCCESS 0 Success 成功 SDK_NULL_ERROR 0x5000 The return value is null error 参数为空，根据错误消息查看具体原因 SDK_CONFIG_ERROR 0x5001 Failed to reading configuration file 检查配置信息是否合法...

图解MySQL 8.0优化器查询转换篇

(l1,l2,l3)IN(SELECT v1,v2,v3.WHERE where)=>EXISTS(SELECT.WHERE where and(l1=v1 or is null v1)and(l2=v2 or is null v2)and(l3=v3 or is null v3)[HAVING is_not_null_test(v1)and is_not_null_test(v2)and is_not_null_test(v3))]...

其他函数

case when shop_name is null then 'default_region' when shop_name like 'hang%' then 'zj_region' end as region from sale_detail;IF表达式命令格式 if(,,)命令说明判断 testCondition 是否为真。如果为真，返回 valueTrue 的值，...

初始化引擎扩展

null){ loadImageListener.onBitmapFailed(new Exception("bitmap is null"));} } }catch(Exception e){ e.printStackTrace();if(loadImageListener!null){ loadImageListener.onBitmapFailed(e);} } } }.start();return url;}@Override ...

SQL基本语法

条件可以包括比较运算符（如等于、大于、小于等）、逻辑运算符（如AND、OR、NOT等）、LIKE模糊查询关键字、IN、NULL判断（如IS NULL、IS NOT NULL等）等。使用比较运算符：当使用等于运算符（=）时，会返回精确匹配的行数据。例如：您可以...

DBMS_SESSION

IF val IS NULL THEN DBMS_OUTPUT.PUT_LINE('The a of test_ctx has been cleared');END IF;END;a of test_ctx is:1-The a of test_ctx has been cleared LIST_CONTEXT 该存储过程用于返回当前会话的活跃命名空间和上下文列表。语法该存储...

公共错误码

诊断 400 InvalidAppInstanceGroup.NullAppInstanceGroup The app instance group is null.交付组为空。诊断 400 InvalidAppInstanceGroup.NullOrNotPublishedStatus The app instance group does not exist or is not published.交付组不...

alicloud_launch_template

[0,100].io_optimized-(Optional)Whether it is an I/O-optimized instance or not.Optional values:none optimized key_pair_name-(Optional)The name of the key pair.Ignore this parameter for Windows instances.It is null by ...

SQL与Catalog报错问题

本文介绍SQL与Catalog报错相关问题。MySQL Catalog加载很慢或者加载出来的表名为灰色如何解决？报错：Cannot obtain STS token from EMR ...ts as case when `datetime` is null then to_timestamp('1970-01-01 00:00:00')else `datetime`end

Profile性能诊断及优化案例

select i_item_desc,w_warehouse_name,d1.d_week_seq,sum(case when p_promo_sk is null then 1 else 0 end)no_promo,sum(case when p_promo_sk is not null then 1 else 0 end)promo,count(*)total_cnt from inventory join catalog_sales...

创建Token

if(data=null){ throw new RuntimeException("create token error,data is null");} System.out.printf("token:%s,expiredTime:%d",data.getToken(),data.getExpiredTime());} catch(RuntimeException e){ throw e;} catch(Exception e){ ...

Bloom过滤器索引

需要注意的是：布隆过滤器不会对null值建立索引，因此如果你的查询条件中使用 where x is null 类似的语句，则即使在x列建立了布隆过滤器索引，该索引也不会生效。此外，嵌套的列也不支持布隆过滤器索引。删除布隆过滤器索引 DROP ...

偏分析场景的实践和优化

AFTER行级触发器

UPDATE jobhist SET enddate=SYSDATE WHERE empno=:OLD.empno AND enddate IS NULL;INSERT INTO jobhist VALUES(:NEW.empno,SYSDATE,NULL,:NEW.job,:NEW.sal,:NEW.comm,:NEW.deptno,v_chgdesc);ELSIF DELETING THEN v_action:='Deleted';v_...

逻辑数仓SQL语法介绍

a is null is not null 是否为非null。a is not null is distinct from 对比两个值的null安全运算符，避免返回空结果，返回结果必定为true或false。select null is distinct from null is not distinct from 对比两个值的NULL安全运算符，...

跨库查询（Beta）

SELECT um.srvname AS"Server",um.usename AS"User name",CASE WHEN umoptions IS NULL THEN '' ELSE '('|pg_catalog.array_to_string(ARRAY(SELECT pg_catalog.quote_ident(option_name)|' '|pg_catalog.quote_literal(option_value)FROM ...

RestoreTable-恢复RDS实例的某些数据库或表到原实例

400 InvalidBakset.Invalid Specified bakset is not valid.-400 InvalidParamTableMeta Invalid parameter TableMeta is null or not json format 参数TableMeta不合法，请检查该参数的正确性。400 InvalidBakHistoryDO BakHistory is ...

RestoreTable-恢复RDS实例的某些数据库或表到原实例

400 InvalidBakset.Invalid Specified bakset is not valid.-400 InvalidParamTableMeta Invalid parameter TableMeta is null or not json format 参数TableMeta不合法，请检查该参数的正确性。400 InvalidBakHistoryDO BakHistory is ...

触发器函数

CREATE TRIGGER emp_stamp BEFORE INSERT OR UPDATE ON emp FOR EACH ROW BEGIN-检查给出了 empname 以及 salary IF NEW.empname IS NULL THEN RAISE EXCEPTION 'empname cannot be null';END IF;IF NEW.salary IS NULL THEN RAISE ...

COMMENT

移除它：COMMENT ON TABLE mytable IS NULL;更多的一些例子：COMMENT ON ACCESS METHOD gin IS 'GIN index access method';COMMENT ON AGGREGATE my_aggregate(double precision)IS 'Computes sample variance';COMMENT ON CAST(text AS ...

在Link TEE上适配ID²

if(aes_ctx=NULL){ HAL_Printf("platform_aes128_encrypt_decrypt aes_ctx is NULL");return-1;} result=ali_aes_get_ctx_size(AES_CBC,&ctx_siz);if(result!ALI_CRYPTO_SUCCESS){ HAL_Printf("get ctx size fail(%08x)",result);return 0;...

记录变量

BEGIN RAISE NOTICE '%',r1 IS NULL;false RAISE NOTICE '%',r1=r2;true RAISE NOTICE '%',r1>r2;false r2.id=10;RAISE NOTICE '%',r1;true END;结果显示如下：NOTICE:f NOTICE:t NOTICE:f NOTICE:t 记录变量与表的交互如上所述，表中的...

在Link SDK上适配ID²-KM

if(aes_ctx=NULL){ HAL_Printf("platform_aes128_encrypt_decrypt aes_ctx is NULL");return-1;} result=ali_aes_get_ctx_size(AES_CBC,&ctx_siz);if(result!ALI_CRYPTO_SUCCESS){ HAL_Printf("get ctx size fail(%08x)",result);return 0;...

通用参考

SPL语句*|extend withoutStatus=(status is null)输入数据#条目1 status:'200' code:'Success'#条目2 code:'Success' 输出结果#条目1 status:'200' code:'Success' withoutStatus:false#条目2 code:'Success' withoutStatus:true 计算过程...

支持的函数

value IS NULL 如果值为NULL返回true。value IS NOT NULL 如果值不为NULL返回true。value1 IS DISTINCT FROM value2 value1和value2的数据类型和值不相同，则返回true。所有NULL值视为彼此相等。value1 IS NOT DISTINCT FROM value2 value1...

远程双录

if(rtcEngine=null){ throw new RuntimeException("rtcEngine is null");} this.inputStream=inputStream;unpublishConfig.videoSource=publishVideoSource;}@Override public void onCustomAudioRecordStarted(ByteBuffer byteBuffer){/...

设置列索引查询过滤算法

注意事项集群版本为 PolarDB MySQL版 8.0.1.1.32及以下或8.0.2.2.13及以下的版本时，对包含NULL值的数据块不会构建任何类型的pruner，并且不支持 IS NULL 或 IS NOT NULL 过滤条件。集群版本为 PolarDB MySQL版 8.0.1.1.35及以上或8.0.2.2...

公共错误码

诊断 403 RuleGroupsNotExist The specified rule groups does not exist.-诊断 403 RuleMatchValueNullError The value of the rule is null-诊断 403 RuleNameInvalidError The name of rule is invalid-诊断 403 RuleQueryParamError ...

系统信息函数和运算符

pg_is_other_temp_schema(oid)→boolean 如果给定的OID是另一个会话的临时模式的OID则返回真。（这可能是有用的，例如，在目录显示中排除其他会话的临时表）。pg_jit_available()→boolean 如果JIT编译器扩展可用，并且jit配置参数设置为 ...

is_null()

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