query count(*) failed

[giant-panda666]

A table stored in TiFlash, using this query sometimes works, sometimes not.

[JaySon-Huang]

Hi @giant-panda666, thank you for pointing out that such an issue exists. Can you provide more information? For example:

• the tidb cluster version
• the related error message contains check failure logging in tiflash.log

[giant-panda666]

1. tidb cluster version is v7.5.2 deployed by tidb operator on k8s.
2. logs.txt

[Lloyd-Pottiger]

@giant-panda666 The following is a workaround:

set tidb_opt_enable_late_materialization = off; <query>; set tidb_opt_enable_late_materialization = on;

Could you please provide the table schema?

[giant-panda666]

@giant-panda666 The following is a workaround:

set tidb_opt_enable_late_materialization = off; <query>; set tidb_opt_enable_late_materialization = on;

Could you please provide the table schema?

The table structure contains sensitive data. Can I obfuscate the field names and enum values before providing them? For example, I can rename the ‘price’ field to ‘a’. Also, could you explain why disabling tidb_opt_enable_late_materialization can temporarily resolve this issue?

[Lloyd-Pottiger]

The table structure contains sensitive data. Can I obfuscate the field names and enum values before providing them? For example, I can rename the ‘price’ field to ‘a’.

Yes.

Also, could you explain why disabling tidb_opt_enable_late_materialization can temporarily resolve this issue?

Only late materialization will call hstackBlocks.

[giant-panda666]

The table structure contains sensitive data. Can I obfuscate the field names and enum values before providing them? For example, I can rename the ‘price’ field to ‘a’.

Yes.

CREATE TABLE separate_order (
id bigint(20) unsigned NOT NULL,
created_at timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
updated_at timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
c0 enum('DEFAULT','E1','E2','E3','E4','E5','E6') NOT NULL DEFAULT 'DEFAULT',
c1 bigint(20) unsigned NOT NULL DEFAULT '0' ,
c2 tinyint(4) NOT NULL DEFAULT '0',
c3 bigint(20) unsigned NOT NULL DEFAULT '0',
c4 bigint(20) unsigned NOT NULL DEFAULT '0',
c5 enum('DEFAULT','E1','E2','E3','E4','E5','E6','E6') NOT NULL DEFAULT 'DEFAULT',
c6 bigint(20) unsigned NOT NULL DEFAULT '0',
c7 varchar(512) NOT NULL DEFAULT '',
c8 varchar(512) NOT NULL DEFAULT '',
c9 enum('DEFAULT','E1','E2','E3','E4','E5','E6','E7','E8','E9') NOT NULL DEFAULT 'DEFAULT',
c10 bigint(20) unsigned NOT NULL DEFAULT '0',
c11 enum('DEFAULT','BALANCE','WX_MCH','GLOBAL_DEPOSIT_ACCOUNT') NOT NULL DEFAULT 'DEFAULT',
c12 timestamp NULL DEFAULT NULL,
c13 bigint(20) unsigned NOT NULL DEFAULT '0',
c14 timestamp NULL DEFAULT NULL ,
c15 decimal(20,4) NOT NULL DEFAULT '0.0000',
c16 decimal(20,4) NOT NULL DEFAULT '0.0000',
c17 decimal(20,4) NOT NULL DEFAULT '0.0000',
c18 enum('E0','E1','E2','E3','E4','E5','E6','E7','E8') NOT NULL DEFAULT 'E0',
c19 int(11) NOT NULL DEFAULT '0',
c20 varchar(1024) NOT NULL DEFAULT '',
c21 varchar(256) NOT NULL DEFAULT '',
c22 smallint(5) unsigned NOT NULL DEFAULT '0',
c23 bigint(20) unsigned NOT NULL DEFAULT '0',
c24 bigint(20) unsigned NOT NULL DEFAULT '0',
c25 bigint(20) unsigned NOT NULL DEFAULT '0',
c26 enum('DEFAULT','E1','E2') NOT NULL DEFAULT 'DEFAULT',
c27 enum('DEFAULT','E1','E2') NOT NULL DEFAULT 'DEFAULT',
c28 enum('DEFAULT','E1','E2') NOT NULL DEFAULT 'DEFAULT',
c29 enum('DEFAULT','E1','E2') NOT NULL DEFAULT 'DEFAULT',
PRIMARY KEY (id) /*T![clustered_index] NONCLUSTERED */,
KEY idx_c1 (c1),
KEY idx_c10 (c10),
KEY idx_c13 (c13),
KEY idx_created_at (created_at),
KEY idx_updated_at (updated_at)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin

[Lloyd-Pottiger]

@giant-panda666 Thanks, you may also need to transform the query.

[giant-panda666]

@giant-panda666 Thanks, you may also need to transform the query.

SELECT COUNT(*) FROM separate_order WHERE c18 = "E7" AND c5 = "E4" AND c9 = "E5" AND c12 IS NULL AND updated_at > date_add(curdate(), INTERVAL - 2 day);

[giant-panda666]

So updating to v7.5.3 will be ok?

[Lloyd-Pottiger]

So updating to v7.5.3 will be ok?

Sorry, I made a mistake, I am still working on it.

[giant-panda666]

It's ok, looking forward to the next version release. Thank you!