Плавающая ошибка

Здравствуйте!
У нас на рабочей базе, в которой ходят одновременно 50 пользователей, время от времени выдается такая вот ошибка:
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Error Обработка Невозможно выбрать запись в "Журнал накладных от поставщиков" ("VendInvoiceJour") Накладная: , .
База данных SQL обнаружила ошибку.
Info Обработка Описание ошибки SQL: [Microsoft][ODBC SQL Server Driver][SQL Server]Syntax error converting datetime from character string.
Info Обработка Оператор SQL: SELECT A.VENDGROUP,A.PURCHID,A.ORDERACCOUNT,A.INVOICEACCOUNT,A.INVOICEID,A.INVOICEDATE,A.DUEDATE, A.CASHDISC,A.CASHDISCDATE,A.QTY,A.VOLUME,A.WEIGHT,A.SUMLINEDISC,A.SALESBALANCE,A.ENDDISC, A.INVOICEAMOUNT,A.CURRENCYCODE,A.EXCHRATE,A.RETURNITEMNUM,A.TAXROUNDOFF,A.LEDGERVOUCHER, A.DIMENSION,A.DIMENSION2_,A.DIMENSION3_,A.TAXPRINTONINVOICE,A.TAXSPECIFYBYLINE,A.DOCUMENTNUM, A.DOCUMENTDATE,A.COUNTRY,A.INTRASTATDISPATCH,A.INVOICEROUNDOFF,A.SUMMARKUP,A.PAYMID, A.TAXGROUP,A.CASHDISCCODE,A.PAYMENT,A.POSTINGPROFILE,A.TAXSPECIFYTOTAL,A.PAYMENTSCHED, A.PURCHASETYPE,A.SUMTAX,A.PARMID,A.ITEMBUYERGROUPID,A.VATNUM,A.INTERNALINVOICEID, A.NUMBERSEQUENCEGROUP,A.INCLTAX,A.PAYMDAYID,A.DLVTERM,A.DLVMODE,A.OCRLINE,A.FIXEDDUEDATE, A.PRINTORIGINALS,A.PRINTCOPIES,A.NONREALREVENUE_RU,A.OFFSESSIONID_RU,A.CONSIGNEEACCOUNT_RU, A.CONSIGNORACCOUNT_RU,A.FACTUREDFULLY_RU,A.ATTORNEYISSUEDNAME_RU,A.ATTORNEYID_RU, A.ATTORNEYDATE_RU,A.RCONTRACTCODE,A.RCONTRACTACCOUNT,A.RECVERSION,A.RECID,B.INVOICEID, B.INVOICEDATE,B.LINENUM,B.INVENTTRANSID,B.ITEMID,B.EXTERNALITEMID,B.NAME,B.TAXGROUP, B.CURRENCYCODE,B.PRICEUNIT,B.QTY,B.PURCHPRICE,B.DISCPERCENT,B.DISCAMOUNT,B.LINEAMOUNT, B.LEDGERACCOUNT,B.TAXAMOUNT,B.DIMENSION,B.DIMENSION2_,B.DIMENSION3_,B.QTYPHYSICAL, B.PARTDELIVERY,B.PURCHID,B.PURCHUNIT,B.PURCHMARKUP,B.TRANSACTIONCODE,B.DESTSTATE, B.TAXWRITECODE,B.TAXAUTOGENERATED,B.TAXITEMGROUP,B.MULTILNDISC,B.MULTILNPERCENT, B.LINEDISC,B.LINEPERCENT,B.ORIGPURCHID,B.TRANSPORT,B.INTERNALINVOICEID,B.NUMBERSEQUENCEGROUP, B.INVENTDIMID,B.LINEAMOUNTTAX,B.PORT,B.STATPROCID,B.INVENTDATE,B.DESTCOUNTY,B.EXCISEVALUE_RU, B.VATVALUE_RU,B.EXCISEAMOUNT_RU,B.VATAMOUNT_RU,B.FACTUREDQTY_RU,B.FACTUREDFULLY_RU, B.REFRETURNINVOICETRANS_W,B.VATDOCUMENTTYPE_RU,B.A_PURCHQTY,B.RECVERSION,B.RECID, C.INVENTDIMID,C.INVENTBATCHID,C.WMSLOCATIONID,C.WMSPALLETID,C.INVENTSERIALID, C.INVENTLOCATIONID,C.CONFIGID,C.INVENTSIZEID,C.INVENTCOLORID,C.INVENTGTDID_RU, C.A_TRANSPORTORDERID,C.A_EXAMACTNUMBER,C.RECVERSION,C.RECID FROM VENDINVOICEJOUR A(NOLOCK) ,VENDINVOICETRANS B(NOLOCK) ,INVENTDIM C(NOLOCK) WHERE ((A.DATAAREAID='tlb') AND (((((A.INVOICEACCOUNT='000068_039') AND (A.PURCHID=' ZP000019')) AND (A.INVOICEID=' H-43')) AND (A.INVOICEDATE={ts '2006-06-19 00:00:00.000'})) AND (((((((((((((((((({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.010.04%' ESCAPE '\' ) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.010.03%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.012.02%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.020.02%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.030.04%' ESCAPE '\' )) OR (0 LIKE {ts '1942-66-49 00:00:00.000'} ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.045.02%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.050.02%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.050.03%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.055.03%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.055.04%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.059.02%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.110.01%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.110.02%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%A03.120.01%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%T00.000.01%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%T00.000.02%' ESCAPE '\' )) OR ({fn ifnull({fn LTRIM(A.INTERNALINVOICEID)},A.INTERNALINVOICEID)} LIKE '%Z00.000.01%' ESCAPE '\' )))) AND ((B.DATAAREAID='tlb') AND ((((((B.PURCHID=' ZP000019') AND (A.PURCHID=B.PURCHID)) AND (A.INVOICEID=B.INVOICEID)) AND (A.INVOICEDATE=B.INVOICEDATE)) AND (A.NUMBERSEQUENCEGROUP=B.NUMBERSEQUENCEGROUP)) AND (A.INTERNALINVOICEID=B.INTERNALINVOICEID))) AND ((C.DATAAREAID='tlb') AND ((C.INVENTLOCATIONID='A03.010.03') AND (B.INVENTDIMID=C.INVENTDIMID))) ORDER BY A.DATAAREAID,A.INVOICEID,A.INVOICEDATE,A.NUMBERSEQUENCEGROUP OPTION(FAST 6)
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Но если подождать некоторое время, то этот же запрос проходит успешно.
Есть подозрение, что возникают какие-то блокировки, но куда смотреть чтобы понять суть происходящего и как это можно исправить?